My education program had us in the classroom for three years to various degrees. This was great. One tip that I can give for an effective way to communicate when time is short is to have a notebook/journal that can be used by both the student teacher and master teacher. During observations/breaks I found I had many questions, but no time to talk to my cooperating teacher. Instead of having all the questions at once, we used a notebook to jot down questions/concerns. This allowed us each to read and respond when time allowed. During my full time student teaching, we also had a weekly meeting scheduled so that nothing was left undiscussed or with any confusion. The notebook served as a great reminder of questions/struggles and triumphs that happened throughout the week. Keep your chin up and ask any and all questions you have!