In this activity, learners explore how engineering has developed various means to remove impurities from water. Learners work in teams of "engineers" to design and build their own "filtration system" out of everyday items. Working with "muddy" water, learners develop a design, and then build and test a system to remove as much impurities from the water as possible. Learners view their own tests and those of other teams, evaluate their results, and present findings to the group. The group with the clearest "filtered" water is considered to have developed the best filter system.
Safety note: Be sure to stress that the "filtered" water, no matter how clear, is not suitable for drinking. For younger students, do not provide charcoal as a filtration option.