by Naomi White, Science Teacher, Jefferson High School, LAUSD

LESSSON SHEET

[ Student Handout ]

Time Frame: one period

Concept:
Humans have a responsibility to treat water after polluting it. While watertreatment mainly involves simple techniques, removing heavy metals is adifficult and often impossible task. Industry must find ways to keepchemicals out of the water supply.

Objective:
Students will use critical thinking skills to try to clean a sample ofdirty water. There is no wrong or right way. Students should use their ownideas to develop technology of sewage treatment.

Materials:

Per Group:

jar of dirty water

pail

Available should students request it (but out of sight):

paper towels, funnels, cotton, other containers, gravel, paper cups,charcoal, screens, hot plate, pot, glass tubing, test tubes,stoppers.

Procedure:

Give students a sample of dirty water including mud, rocks, andperhaps some paint. Tell them that they are to find a way to clean it. Ifthey need other equipment, they can request it if available. After theyhave had a chance to solve the problem, discuss with the class thetechniques that they used. Discuss what was hardest to get out of the water(mud, rock, paint). Explain actual sewage treatment techniques and discussproblems that water pollution and in particular chemical pollutantspose.