What I am about to say may appear foren and definitely out of the box. You will need to understand what you put in the unit and areas around it as some of your students will. I have no idea what resources you have available but I assume, a phone, a computer and pencil and paper. Go on line and find several manufacturers of microprocessors such as Ti, Siemens, Atmel etc. Go to there web sites and download app notes and read them. Most of these companies have FAE's (Field Application Engineer) , See if you can connect with a few, they have unbelievable knowledge on this stuff. Contact them and see if they can help you even by simply sending you to locations for information or explaining terms but do your homework first and look them up. Several of these companies also offer teaching materials etc for schools typically at no charge. Most do this at the beyond high school level several may do it at the high school level. It will cost you nothing to try and what you learn will be unbelievable. I have two sons that were so far beyond there teacher in compute science it was embarrassing for the teachers. If you get a technical expert that tells you he/she does not know the answer but will get it for you then does hang on you have one of the very few really good ones. I see many mistooks in the answers given by people in these forums by people that trying to help but do not fully understand. This response is to help you get started in solving your problem, not solve it for you.
Good Luck & Have Fun!
Gil