do you think that working on signal transduction for 9th graders is a bad idea to enter a science project? got an awesome project on mind but the science department head won't allow it because I haven't taken previous biotechnological lab courses.

Signal transduction may be too difficult of a subject for 9th graders to work on, though it would depend what your project actually is. Signal transduction involves some fairly sophisticated molecular biology which may be beyond the scope of a high school student. Perhaps if you post more details on your project, we would be able to let you know how feasible it is.