I need help! I have a project to do on solar devices!?

My teacher has tol me to do a project on slar devices. I need to make atleast two models. I want to make a solar cell and a solar water heater. Can someone tell me how to make them, plsss. I have only 10 more days for my school to reopen. so withn 10 days i need to make those two. So it should be simple and easy to make. Please ppl, help!