Suggested Grades

Any

Objective

Student’s will observe and learn about how and how quickly germs spread from person to person.

Materials

• grass growing in four separate trays (plant grass seeds in soil on meat trays or something similar about two weeks in advance)
• distilled or bottled water
• tap water
• a mixture of 1 part weak orange juice and 4 parts water
• a mixture of equal parts of vinegar and water.
• recording sheets

Method

• When grass has grown enough to see that it is in fact grass begin watering each tray with their own type of liquid every day.
  tray 1: distilled or bottled water
  tray 2: tap water
  tray 3: orange juice water
  tray 4: vinegar water
  
• Every day have students record their observations of each tray by drawing how the grass looks and/or writing key words.
• After noticeable effects have occurred have a class discussion on what happened to each tray of grass and why. The tray that was watered with the vinegar water should have fared the worst.
• Then move the discussion to how acid rain is similar to the orange juice and the vinegar water. Discuss what will happen if we let acid rain to continue to form and ways to prevent it from falling on our plants and us.