If you teach environmental science or APES (Advanced Placement Environmental Science) you may want to check out the following link:
The site is designed to be an online APES class and claims to cover all of the material the College Board dictates must be covered for APES. I haven’t looked through the entire site myself, so I can’t speak for that assertion. However, there are some neat online labs where students have to change inputs and then assess what happens, and so on. Check it out.