Students explore the differences between lentic and lotic ecosystems. In this ecology lesson students study the water systems in Pennsylvania.

Students assemble a classroom river model as an example of a lotic system. They control and measure biotic and abiotic information for the in-class system and compare data with a lotic system in a natural environment.

Students create and conduct experiments on a "classroom river habitat." They manipulate the biotic and abiotic factors so that they are able to compare an artificially prepared river model to a naturally occurring lotic ecosystem.