1、One possible version:

     As we know, when junior students graduate from school, most of their reference books as well as textbooks are thrown away. They are still useful. What a great waste it is!

     I suggest that we should recycle these books. On one hand, they can be used again and again, recycling them can save a lot of natural resources. On the other hand, junior students may have made plenty of useful notes on the pages. They are very helpful to the following users. In fact, in Australia and some other countries, recycling textbooks is popular, which gives us a good example. It can help many poor village students to continue their study.

     At present, the whole nation is called on to build an energy-saving society. I hope more and more students can join me and do something for it.