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What can we do for science education?


Cap'n Refsmmat

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I just got back from tutoring students at a local high school. It was an event for students specifically taking AP classes, which culminate in an exam which is accepted for credit by many universities. The students are generally high school seniors -- 17 or 18.

 

Every student had a TI-89 calculator which they used to solve every problem. At one point, a student was working out some arithmetic and encountered this:

 

[math]2\times \frac{4}{5} =\; ?[/math]

 

She paused, looked uncertain, and said "well, I don't know that off the top of my head" and reached for her calculator.

 

I'd ask other students "okay, now solve that equation for t" and they'd stare at me blankly, before reaching for their calculator to type "solve(4.9t^2 = 10, t)".

 

They had trouble with basic physics concepts. For example, a force that acts perpendicular to the direction an object travels does no work -- it doesn't contribute to the object's motion. (For example, if a block slides along the ground and you push straight down on the block, you're not doing work on it.) They were utterly surprised when their calculator gave them zero.

 

Many didn't get the concept of inverse sines and cosines, despite having done trigonometry for months.

 

You can see why I'm worried about the state of education. Most of this is basic algebra and arithmetic, and yet these high-school seniors couldn't do it without their TI-89s. They had passed their state standardized tests, passed their algebra classes, gotten into an advanced placement course -- and they can't multiply fractions.

 

What can we, as people in the science community, do? What can educators do to change this? We can't just make the tests harder -- they'll all fail. There's something structurally wrong with how we teach high schoolers.

 

I'm curious to hear if anyone else has had similar experiences as well.

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I just got back from tutoring students at a local high school. It was an event for students specifically taking AP classes, which culminate in an exam which is accepted for credit by many universities. The students are generally high school seniors -- 17 or 18.

 

Every student had a TI-89 calculator which they used to solve every problem. At one point, a student was working out some arithmetic and encountered this:

 

[math]2\times \frac{4}{5} =\; ?[/math]

 

She paused, looked uncertain, and said "well, I don't know that off the top of my head" and reached for her calculator.

 

I'd ask other students "okay, now solve that equation for t" and they'd stare at me blankly, before reaching for their calculator to type "solve(4.9t^2 = 10, t)".

 

They had trouble with basic physics concepts. For example, a force that acts perpendicular to the direction an object travels does no work -- it doesn't contribute to the object's motion. (For example, if a block slides along the ground and you push straight down on the block, you're not doing work on it.) They were utterly surprised when their calculator gave them zero.

 

Many didn't get the concept of inverse sines and cosines, despite having done trigonometry for months.

 

You can see why I'm worried about the state of education. Most of this is basic algebra and arithmetic, and yet these high-school seniors couldn't do it without their TI-89s. They had passed their state standardized tests, passed their algebra classes, gotten into an advanced placement course -- and they can't multiply fractions.

 

What can we, as people in the science community, do? What can educators do to change this? We can't just make the tests harder -- they'll all fail. There's something structurally wrong with how we teach high schoolers.

 

I'm curious to hear if anyone else has had similar experiences as well.

 

I don't have any suggestions as of now.

 

I'mJust posting to say that I second your sentiment here.

 

Last year I tutored high school math (mostly algebra, trig and easy differential calculus) and ran into similar problems. High schools students never seemed to get any of the geometric arguments behind the trig functions and never seemed to grasp how the inverse trig functions output angles.

 

Multiplying fractions and rules for manipulating roots, logs, and exponents seem to be lost on blank faces. I believe these mathematics inadequacies are some of the major contributing factors to the physics/chemistry education crisis.

 

Calculators are great but I do think they contribute to intellectual laziness when introduced too early. Many fraction operations and simple algebraic manipulations can even be done faster by old fashioned "head power". I understand using a calculator to multiply/divide 6-digit numbers or evaluate nasty transcendentals (like [math] \cos\frac{37\pi}{114} [/math]), but using one to do arithmetic operations on simple fractions is ridiculous.

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I don't really see a problem with students using calculators if it is a valid method to solve the problem at hand. I have no idea what an "AP class" is, btw ("Advanced Physics" ?).

 

In the US. "AP" stands for "advanced placement", meaning a high-school course that is closer to what one would experience in a first year university course.

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I am old enough to have to have experienced just about all of my education prior to the introduction of electronic calculators. My earliest device for making calculations easy was a slide rule (I still have mine). You couldn't use a slide rule without making an approximate calculation first because the slide rule could not give you the position of the decimal point. We were thus forced to understand and use basic mathematics if we wanted to use the slide rule. Sometimes it seems a step forward is not as beneficial as we think.

However, although I prefer and use an electronic calculator, I still pause long enough to consider whether the result is sensible. That is something that people brought up on calculators don't seem to do.

Edited by TonyMcC
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I don't really see a problem with students using calculators if it is a valid method to solve the problem at hand. I have no idea what an "AP class" is, btw ("Advanced Physics" ?).

Calculators are not permitted on a large portion of the AP physics exam. The AP exam is a standardized exam which many universities accept for college course credit:

 

http://www.collegeboard.com/student/testing/ap/sub_physb.html

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I think it's obvious that a decade of No Child Left Behind has had disastrous results on the nation's publicly schooled students. IMO, there has been a concerted effort to make public education look bad in order to encourage privatization. Stop those efforts by any means possible first; this will clear the way for a proper foundation any future changes can rest upon.

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Calculators are not permitted on a large portion of the AP physics exam.
If your focus is on preparing for an exam then train under exam conditions - possibly even time constraints. Your student who doesn't know "2*4/5" out of the top of her head will surely find a way to evaluate it if there is no pocket calculator at hand - and she better finds that way before the actual exam.

 

Since I've never been to the US, less taught physics or math there, I can of course not comment on the general situation of "students don't learn anything anymore". I do realize that some of the experiences you describe in your OP are strange or disturbing. But you should (a) keep in mind that not all of these issues apply to all students, and (b) for each of them ask yourself if they really matter in the end. If your strongest argument against using a calculator is that the calculator is not allowed in the exam, then perhaps using a calculator is not that much of a real problem.

 

Considering the in my eyes more real problems like students not knowing that a force that is perpendicular to displacement does no work: You sometimes do have to tell students (or colleagues ;) ) things that they are actually supposed to know (*). "You passed an exam about it so you must know it" is a very typical teacher attitude. But I also find it very arrogant and think that it does not take into account that students are human individuals with their own ideas and their own ways to connect information, and may therefore put different priorities (than you) on the lot of material that they are presented(*). Accept it, and see it as your chance to get the point across better than that last guy who obviously failed. A good teacher must pick up their students where they stand, I think.

 

Please note that I am not trying to attack you here. It's more like playing the devil's high-school student's advocate. It's pretty easy just to tune into the "the kids of today are all so stupid" canon and tell stories about stupid students encountered. But without reflection it is also pretty lame to do so.

 

(*) Two weeks ago I helped two of our grad students who had struggled for an hour to compile some code. Took less than one minute to find the solution on Google. And "yes", grad students are expected to be able to use Google without supervision.

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I'm not trying to argue against using calculators, and I hope I didn't come across as attacking the students. They're surely capable of doing algebra and arithmetic should they have an opportunity to learn and practice. Somehow our education system isn't giving them that opportunity. The use of calculators to do basic algebra is merely a symptom of this.

 

"You passed an exam about it so you must know it" is a very typical teacher attitude. But I also find it very arrogant and think that it does not take into account that students are human individuals with their own ideas and their own ways to connect information, and may therefore put different priorities (than you) on the lot of material that they are presented(*). Accept it, and see it as your chance to get the point across better than that last guy who obviously failed. A good teacher must pick up their students where they stand, I think.

I agree. I'm concerned more about the system which doesn't successfully accommodate these differences. We're designing courses which students take and pass without gaining a fundamental understanding of the material. This is a problem with how we teach, not how they learn. How do we teach better?

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Calculators are a mess sometimes. Like, in this case, if on the very first day the student was doing the problem and encountered the fraction operation and went for a 'I will try again' than 'Where is the damn calculator'- he would have been a success in it today.

I don't know about how books in your country are designed. But, here we have books which repeat stuff, though adding a little to it, in alternate classes. Like, if in class 8 I learnt about various types of cells and how they function, I would learn about electricity in detail-with concept of resistance, voltage, power and all. If I learnt about how lens and mirrors work, just the basics; I would learn the mirror formula and lens formula in 10 and in 12 I would be deriving them all.

The problem might be in the book designing part.

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There are a number of problems that contribute to what you observe.

 

1. Many secondary school teachers, even mathematics and physics teachers are incompetent in science and mathematics. People who are competent in mathematics and science but who do not hold teaching certificates are often not permitted to teach in the public school system, even though they would be qualified to teach the same subjects in a university setting.

 

2. There is an excess reliance on computers and calculators as "black boxes". This unfortunately extends to some mathematics classes. Students tend therefore to lack fundamental understanding even if they can "find the answer" to textbook problems. Lack of competence on the part of teachers tends to promulgate this problem.

 

3 The curriculum has been watered down. Real credit at some discerning schools is not given for AP scores below the top level of "5". This untimately comes back to people teaching subjects in which they lack competence.

 

4. Much AP emphasis, in calculus in particular is on symbol manipulation rather than understanding. The result is that students who learn their calculus at a university tend to have deeper understanding that those who learn it in AP calculus -- this opinion was confirmed to me by an MIT engineering professor. In short, AP classes by themselves are not the answer.

 

If you want to improve the situation the place to start is with the competence of secondary school teachers in mathematics and science. The major research university in my state has a project to do this. Initially it was headed by a well-known mathematician, but I don't know if he felt he made much progress, and it is now going in to a longer term phase.

 

I don't really see a problem with students using calculators if it is a valid method to solve the problem at hand. I have no idea what an "AP class" is, btw ("Advanced Physics" ?).

 

When students can't do simple arithmetic calculations quickly in their head they have no hope of being able to follow a lecturer in a derivation of nearly anything. It is a BIG problem in terms of understanding.

 

Simple example: Students often have trouble with fractional exponents -- because they can't add fractions.

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I'm not trying to argue against using calculators, and I hope I didn't come across as attacking the students. They're surely capable of doing algebra and arithmetic should they have an opportunity to learn and practice. Somehow our education system isn't giving them that opportunity. The use of calculators to do basic algebra is merely a symptom of this.

 

 

I agree. I'm concerned more about the system which doesn't successfully accommodate these differences. We're designing courses which students take and pass without gaining a fundamental understanding of the material. This is a problem with how we teach, not how they learn. How do we teach better?

 

idk, do you think maybe the calculators arent a symptom, but the cause?

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1. Many secondary school teachers, even mathematics and physics teachers are incompetent in science and mathematics. People who are competent in mathematics and science but who do not hold teaching certificates are often not permitted to teach in the public school system, even though they would be qualified to teach the same subjects in a university setting.

Here in Texas, high school science and math teachers are required to have an undergraduate degree in science or math along with their teaching certification. (Texas state schools don't offer education degrees.) There's no guarantee that you won't get, say, a biology major teaching an advanced-placement physics class (as happened to me -- he ended up being removed ten weeks into the year), but in general teachers have more competence than just the introductory science classes they were required to take for their education degree.

 

If a state were to require physics teachers to have physics degrees and math teachers to have math degrees and so on, it would need essentially the entire physics major output of its universities just to provide teachers. That's not going to happen until teaching pays as well as the numerous alternatives.

 

I'll also note that I've had quite a few incompetent lecturers in university, where they're nearly all tenured professors. I think we're missing something more fundamental than "knows math and science well."

 

2. There is an excess reliance on computers and calculators as "black boxes". This unfortunately extends to some mathematics classes. Students tend therefore to lack fundamental understanding even if they can "find the answer" to textbook problems. Lack of competence on the part of teachers tends to promulgate this problem.

Do you think this is the cause or the symptom? If these students were taught algebra without calculators, but are now entirely dependent on them to do basic algebra, something went wrong in the pre-calculator teaching. If they were taught to do algebra by using their graphing calculators to type "solve()", then some teachers should be taken out and shot.

 

If you want to improve the situation the place to start is with the competence of secondary school teachers in mathematics and science. The major research university in my state has a project to do this. Initially it was headed by a well-known mathematician, but I don't know if he felt he made much progress, and it is now going in to a longer term phase.

Yes, our university is running a program to get science majors teaching certifications before they graduate, so they have an undergraduate science degree and are licensed to teach immediately. It's moderately popular and they're working to expand it.

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In my experience a large part of the problem is that a lot of education is so compartmentalised.

 

They get 'today we're doing trig identities' in maths class, and that's all they do.

Nothing else in their education is required for that unit, and it isn't applied anywhere else.

 

When I tutor highschool and first year uni (14 - 17 y.o) students I find they can solve the equations, and multiply constants by fractions, but it requires a significant amount of goading and encouragement.

The usual conversation goes something like:

"Now, do you remember from maths last year/in year 10/etc how to solve an equation like this for t?"

"But we're doing physics, not maths."

After the exam on any given unit they (perhaps rightly as they are rarely contradicted in this) come to the conclusion that they will never need that piece of information again and stop paying any attention to it.

 

Another thing that comes up a lot is 'are we allowed to do that?'

They get so used to only using (and only being allowed to use, even if they see another way around) a single method on a single type of problem that they think it must be cheating to use knowledge external to the unit they are doing.

 

The third major issue I've seen (mostly in physics and maths) is that very little attention is paid to what they are actually doing.

Barring a few contrived problems at the end of the chapter there isn't really any context or reason behind what they are learning.

On top of this, no attention is paid to understanding the methods that are being applied. The focus is instead on performing a series of steps memorized by rote.

 

2. There is an excess reliance on computers and calculators as "black boxes". This unfortunately extends to some mathematics classes. Students tend therefore to lack fundamental understanding even if they can "find the answer" to textbook problems. Lack of competence on the part of teachers tends to promulgate this problem.

 

When students can't do simple arithmetic calculations quickly in their head they have no hope of being able to follow a lecturer in a derivation of nearly anything. It is a BIG problem in terms of understanding.

 

Simple example: Students often have trouble with fractional exponents -- because they can't add fractions.

 

I'm not convinced the calculators are at fault here.

When deprived of a calculator, many students will fall back on some algorithm or method that they learned by rote to do whatever it is they are doing.

This is often just as much of a black box as a calculator (they put the numbers in, crank the handle, even if the handle is in their head, and the answer pops out).

 

Much of their mathematical knowledge seems to be stored as a big list of rules (ie. when adding fractions you cross multiply) with no reason or rationale behind them other than 'the book said so'.

This becomes quite apparent when you look at the mistakes being made (ie. cross multiplying fractions whenever they are encountered even if they already have a common denominator or are being divided etc).

The calculator merely allows people to limp along for a few more years (basically by acting as external storage for their list of rules) where otherwise they would have failed years ago.

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Sometimes I feel like my opinion isn't relevant, because I'm not qualified... but here I'm kinda at the other end.

 

Goodness, I remember something changed when I actually, 100% genuinely realized I could apply a method elsewhere, or even the simple fact that I could use a different method to get the same result with my own free will, and it wasn't seemingly insignificant memorization for tomorrow's test... there was actual unwavering reason behind it? I know it sounds ridiculous but I think this is how a lot of young students think.

 

IMO, using calculators takes away from understanding math for what it is! And with that, your understanding doesn't build magnificently over time.... you just memorize chunks that don't fit together. At least that's what it felt like to me.

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Much of their mathematical knowledge seems to be stored as a big list of rules

 

 

Which is understandable when you consider that many of their teachers have no deeper understanding.

 

As I said, the problem starts with incompetent secondary school teachers.

 

The calculator is but a symptom, but an important symptom.

 

I'll also note that I've had quite a few incompetent lecturers in university, where they're nearly all tenured professors. I think we're missing something more fundamental than "knows math and science well."

 

 

 

I rather doubt that they were incompetent in their own field, at least if you are speaking of mathematicians or physicists.

 

Competence in one's field may not be a sufficient condition for a good teacher, but it is a necessary condition. And it is a condition that many secondary teachers fail to meet, even if they have a BS in the discipline.

 

I find complaints about "incompetent lecturers" at the university level suspect. At that level the responsibility of the lecturer is to aid the stufdent in learning, not teach. The failure is quite likely on the part of the student to meet his obligation to learn.

Edited by DrRocket
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I find complaints about "incompetent lecturers" at the university level suspect. At that level the responsibility of the lecturer is to aid the stufdent in learning, not teach. The failure is quite likely on the part of the student to meet his obligation to learn.

They can't be effective in this responsibility if they are utterly incapable of explaining a concept to a student, or of answering questions helpfully.

 

There's a great deal of research on teaching methods at the undergraduate level, particularly in physics, and the majority of it is ignored. Simple changes, like asking students to predict the outcome of a lecture demonstration beforehand or waiting more than three seconds before answering student questions, have been shown to have significant beneficial impacts on student understanding.

 

There are also a number of studies following students in introductory mechanics classes and evaluating their conceptual understanding of the material. Students generally make horribly contorted and confused mental models of basic physics and fit everything they read or hear into the model. (One paper found that many students have difficulty distinguishing between velocity and acceleration -- after months of intro physics.) Once this happens, the student can't possibly succeed in learning for himself, until someone carefully demolishes his faulty model.

 

I can provide a few papers if you'd like.

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There are also a number of studies following students in introductory mechanics classes and evaluating their conceptual understanding of the material. Students generally make horribly contorted and confused mental models of basic physics and fit everything they read or hear into the model. (One paper found that many students have difficulty distinguishing between velocity and acceleration -- after months of intro physics.) Once this happens, the student can't possibly succeed in learning for himself, until someone carefully demolishes his faulty model.

 

Part of the issue (and I think this is what Dr. Rocket may have been getting at) is that this should have been done before the student hits university.

It should be just as much (if not more) the responsibility of the highschool teacher to do this as the university lecturer.

Spending most of first year concentrating on fixing incorrect models and teaching critical reasoning is one way of routing around a faulty primary/secondary school system, but it is symptomatic of a wider issue.

 

This being said I have seen enough lecturers who are bad at teaching and TAs who don't know calculus to see Capn's point.

While this should not be enough to stop a student learning the correct concepts at this level (if the have an adequate background in critical reasoning skills and have already been absolved of their incorrect models), it most certainly does not help the process along.

Part of the issue here is that staff are often required to teach as part of their duties without requiring/being given much in the way of training. While they are invariably intelligent (and capable of learning on their own), the fact that they are obliged to be there means that some of them spend far less time thinking about/researching teaching methods than needed.

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I can provide a few papers if you'd like.

Here's a few examples of the papers I've found. They tell us interesting things about effective teaching methods:

 

 

These studies show useful methods that undergraduate lecturers could use to significantly improve student understanding. We could blame educational failure on a student's inability to learn, but not until we've investigated our own teaching methods.

 

Part of the issue (and I think this is what Dr. Rocket may have been getting at) is that this should have been done before the student hits university.

It should be just as much (if not more) the responsibility of the highschool teacher to do this as the university lecturer.

Spending most of first year concentrating on fixing incorrect models and teaching critical reasoning is one way of routing around a faulty primary/secondary school system, but it is symptomatic of a wider issue.

Indeed. But the same strategies could presumably be adopted in secondary school to prevent the students from developing the misconceptions in the first place.

 

Of course, that puts a tremendous burden on the teacher. Understanding the subject matter isn't enough -- you need the ability to understand the student's understanding of the subject matter, and that can be very difficult to do. It requires a thorough understanding of the subject and an understanding of how students learn it.

 

So I suppose I do agree that we need better-educated and better-prepared teachers who understand their subject exceedingly well. But we also need to change our teaching strategies, because they're not nearly as effective as they should be.

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They can't be effective in this responsibility if they are utterly incapable of explaining a concept to a student, or of answering questions helpfully.

 

 

Some of the best classes that I have taken were taught by what is known as the "Moore method" or "Texas method" in which the burden was fully placed on the student and the lecturer did not explain anything or answer questions. They merely moderated and sometimes contributed to the critique by the class of work presented by the students.

 

I don't believe that any "tenured professor" is incapable of explaining a concept to a student who is actively trying to learn (as opposed to expecting to be "taught") or of answering questions ("helpfully" is in the beye of the beholder and a perfectly reasonable answer may not be recognized as such by a lazy or poor student). There is WAY to much emphasis placed on "self esteem" by many students, and primary and secondary school teachers. Students may not like blunt answers, but sometimes they need to hear them.

 

I repeat, the burden to learn belongs to the student. A great deal of the problems in education lie in the failure of the student to meet that responsibility.

 

What cannot be excused is failure of the instructor to understand the subject matter, and the teaching of distortions and downright falsehoods.

 

There are also a number of studies following students in introductory mechanics classes and evaluating their conceptual understanding of the material. Students generally make horribly contorted and confused mental models of basic physics and fit everything they read or hear into the model. (One paper found that many students have difficulty distinguishing between velocity and acceleration -- after months of intro physics.) Once this happens, the student can't possibly succeed in learning for himself, until someone carefully demolishes his faulty model.

 

 

Then something is horribly wrong in their first class in physics, likely in high school. Veclocity and acceleration are so well-defined and fundamental that only someone who fails completely to understand very basic physics and mathematics could create such confusion. We are back to requiring competence in secondary school teachers.

 

There is also the unfortunate reality that only a minority of U.S. students possess both the capability and inclination to understand any but the most elementary mathematics and science. Capability is probably more ubiquitous than interest, but both are necessary.

Edited by DrRocket
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Some of the best classes that I have taken were taught by what is known as the "Moore method" or "Texas method" in which the burden was fully placed on the student and the lecturer did not explain anything or answer questions. They merely moderated and sometimes contributed to the critique by the class of work presented by the students.

I'm familiar with this method, as I'm typing this sitting in the R.L. Moore building here at UT. I wish I had an opportunity to experience it in my courses, but only a few math professors are willing to put in the time and effort to run a Moore-method class.

 

I don't believe that any "tenured professor" is incapable of explaining a concept to a student who is actively trying to learn (as opposed to expecting to be "taught") or of answering questions ("helpfully" is in the beye of the beholder and a perfectly reasonable answer may not be recognized as such by a lazy or poor student). There is WAY to much emphasis placed on "self esteem" by many students, and primary and secondary school teachers. Students may not like blunt answers, but sometimes they need to hear them.

The answers I see professors give to questions can be placed into several categories:

 

  • An answer to a question completely different from the one asked. This is the most common.
  • An answer given before the student can even finish explaining their question. Most professors start answering as soon as they hear something they can answer, without waiting a moment for the student to finish. (There is, incidentally, some research on waiting before answering. It prompts the student to elaborate and think about their idea some more, and elicits answers from other students, helping the entire class learn from one question.)
  • An answer that requires knowledge of topics that have not been covered or defined. The professor doesn't seem aware of what the students do and do not know.
  • A repetition of what was already said. The student is confused, and the professor just restates what's confusing.
  • An actual answer to the question. The student might not understand it, but it's an answer.
  • A ten-minute speech about things completely unrelated. (My ethics professor was terrible about this.)

 

I don't see how self-esteem enters into it. Blunt answers aren't the problem. Useless answers are.

 

I repeat, the burden to learn belongs to the student. A great deal of the problems in education lie in the failure of the student to meet that responsibility.

And why do you think students are systematically failing to meet their responsibility? Is there something that can be changed to fix this?

 

Then something is horribly wrong in their first class in physics, likely in high school. Veclocity and acceleration are so well-defined and fundamental that only someone who fails completely to understand very basic physics and mathematics could create such confusion. We are back to requiring competence in secondary school teachers.

The studies were performed on students taking calculus-based university physics.

 

Even students who did well on course examinations were frequently unable to demonstrate a qualitative understanding of acceleration as the ratio [math]\Delta v/\Delta t[/math] when asked to apply this concept to an actual motion in the laboratory.

 

I think a decent high-school teacher can produce students capable of easily passing the AP physics exam and passing exams in their university physics courses, but without the students understanding squat about basics of physics.

 

A lot of the research shows that students come to classes with misconceptions produced from general experience, not earlier physics courses -- students think that a force is required to keep an object in constant motion, for example, despite being told about Newton's first law as the first subject in their physics class. Teachers may eloquently explain the correct concept, but misconceptions are robust: the student makes the explanation fit their beliefs, rather than throwing out their incorrect ideas. No amount of competence can lecture away the misconceptions; they need to be handled directly.

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  • A ten-minute speech about things completely unrelated. (My ethics professor was terrible about this.)

When you take a philosophy class all bets are off. One cannot expect any sort of conclusion from a philosopher.

 

 

 

I think a decent high-school teacher can produce students capable of easily passing the AP physics exam and passing exams in their university physics courses, but without the students understanding squat about basics of physics.

 

I cannot imagine a more damning statement about AP physics classes or exams in a university physics class. Which is not say that it is not true, but rather that there is way too little emphasis on understanding and way too much on cook book exercises.

 

A lot of the research shows that students come to classes with misconceptions produced from general experience, not earlier physics courses -- students think that a force is required to keep an object in constant motion, for example, despite being told about Newton's first law as the first subject in their physics class. Teachers may eloquently explain the correct concept, but misconceptions are robust: the student makes the explanation fit their beliefs, rather than throwing out their incorrect ideas. No amount of competence can lecture away the misconceptions; they need to be handled directly.

 

This is even scarier. What is the origin of these misconceptions ? I don't see how high school physics cannot be a significant source, unless the students did not take high school physics. In the latter case I don't quite see how the basis could be a university level calculus-based physics class unless the students simply don't have the appropriate background.

 

In any case this sounds like a serious deficiency in either preparation or reasoning on the part of the students themselves. They cannot possibly be reading and understanding the text or paying attention in lectures and still maintaining such basic misconceptions. Maybe they believe too much of the nonsense that is available on the internet. This is more of a problem with critical thinking than with any specific subject matter, but I suspect it gets back to expectations from primary and secondary school, and maybe too much junk from poor sources.

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This is even scarier. What is the origin of these misconceptions ? I don't see how high school physics cannot be a significant source, unless the students did not take high school physics. In the latter case I don't quite see how the basis could be a university level calculus-based physics class unless the students simply don't have the appropriate background.

 

In any case this sounds like a serious deficiency in either preparation or reasoning on the part of the students themselves. They cannot possibly be reading and understanding the text or paying attention in lectures and still maintaining such basic misconceptions. Maybe they believe too much of the nonsense that is available on the internet. This is more of a problem with critical thinking than with any specific subject matter, but I suspect it gets back to expectations from primary and secondary school, and maybe too much junk from poor sources.

There's a difference between a course actively promoting misconceptions and one which gives the students a poor conceptual understanding of the subject -- though they are quite capable of memorizing equations and grinding out answers -- and leaves them to fill in the conceptual gaps with their own intuitions and invention. I suspect we see far more of the latter. Students learn all about the physics terms, but have little understanding of how they connect to reality and how they can be applied to physical situations.

 

If you'd like to see the examples from the research, here's the citation:

 

McDermott, L. C. (1984). Research on conceptual understanding in mechanics. Physics Today, 37(7), 24. American Institute of Physics. http://physicstoday.org/resource/1/phtoad/v37/i7/p24_s1

 

If you can't get a full-text copy easily, I can send you a PDF.

 

I don't think the blame can be placed solely on the students. Somehow, we're designing courses which students can pass easily with little conceptual understanding, and we're teaching them in a way that encourages them to simply memorize steps to solving problems. We could blame this on the students all we want, but how do we fix it?

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There's a difference between a course actively promoting misconceptions and one which gives the students a poor conceptual understanding of the subject -- though they are quite capable of memorizing equations and grinding out answers -- and leaves them to fill in the conceptual gaps with their own intuitions and invention. I suspect we see far more of the latter. Students learn all about the physics terms, but have little understanding of how they connect to reality and how they can be applied to physical situations.

 

Not surprising.

 

I have been told by students that they had no interest in understanding the theory, but rather just wanted to "plug and chug". I saw a lot more of this attitude in industry and there it is scary because you get people who are good at manipulating sophisticated computer codes, but don't understand what those codes really tell you or what the limitations are.

 

I have seen "equations" derived by PhD's with perfect symbol manipulation -- but having no relationship to the actual question at hand. Right answer. Wrong problem. This is the same student failing but at a higher and more costly level.

 

 

[quote name=Cap'n Refsmmat'If you'd like to see the examples from the research, here's the citation:

 

McDermott, L. C. (1984). Research on conceptual understanding in mechanics. Physics Today, 37(7), 24. American Institute of Physics. http://physicstoday....d/v37/i7/p24_s1

 

If you can't get a full-text copy easily, I can send you a PDF.

 

I don't have access. I would appreciate a PDF. Thanks.

 

I don't think the blame can be placed solely on the students. Somehow, we're designing courses which students can pass easily with little conceptual understanding, and we're teaching them in a way that encourages them to simply memorize steps to solving problems. We could blame this on the students all we want, but how do we fix it?

 

Students seem to more or less demand such courses. You fix it by ignoring such demands and instead run classes with real content, that challenge the students and by failing those who can't or won't meet reasonable standards. This is not hard to do. Text books already exist. It does require that legislatures and administrations recognize that not everyone will meet those standards and that some children will be left behind.

 

What won't work is demanding that educational effectiveness be measured by average scores on standardized texts. When you do that you get exactly the conduct that you incentivize -- people teach the test. There is a real problem with empasis on things other than understanding. http://www.lehigh.edu/~shw2/ap2001.html

 

Students today have the same basic genetics that students have always had, plus ready access to a vast amount of information. If they are weak on critical thinking and deep understanding it is because such has not been demanded of them. Critical thinking is not "taught", it is developed through exercise, and with that excercise comes understanding. One can demand exercise.

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The origin of these misconceptions could be as simple as observation of one's environment. You put a ball into motion, and it will come to rest. Instructors need to assume the responsibility of explaining friction, how things fit into our surroundings, painting the big picture, rationalizing what is seemingly irrational at first. The example of motion/friction is trivial; my point is that this idea should still apply to more complex concepts as much as possible. Maybe some coddling is necessary. An in depth psychological understanding of how students approach material, why they ask the questions they do, how they think, is just as necessary as extensive knowledge of physics. Understanding the audience is just as crucial as understanding the material. You must speak their language.

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