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.
Blog of the Airtightnoodle 