Teachers offering classes on English as a second language -- or just about any other subject -- will benefit from the great resources at eslflow.com, which offers dozens of free lesson plans
covering environmental topics.
The first lesson on the page is a perfect example of what you'll find there -- it's a grammar guide for writing using passive tense using environmental subjects as examples.
After that, there are vocabulary exercises, recycling activities and worksheets, climate change lesson plans, quizzes, information about endangered species, lessons on air pollution, and a whole lot more. There are even fun things, like crosswords.
Seriously, this is a great resource for just about any teacher and just about any class. Give it a look and see what you can do to incorporate these ideas into your own curriculum.