These students are using what they have learned about  ecosystems.
     First, they worked with in groups to classify different components of an ecosystem.  They needed to decide which parts belong in the community and which parts belong in the environment.   They also had to decide which members of the community were producers, consumers, or decomposers.
     Afterward, the groups became teams and they raced to try to be the first team to classify the different components with the fewest errors.