Any of the major biological supply houses have them for sale.
Topics range from anthropogenic pollutants to population and biodiversity.
They also release publications on each of these topics. It is a series of video case studies that vary in length from 5 minutes to about 20 minutes each. There are now several volumes of these case studies available. The students at the school are building model living machines to see if they can be applied to the clean-up of Chattanooga Creek, a local superfund site.