Field Trip Notes
Arnold and Wanda are due to give a report on the town waterworks. But Ms. Frizzle thinks its field trip DRIP time! She turns the bus and class into water drips and the kids evaporate, condense, rain down miles from home, and rush through rivers and streams toward the ocean. After several trips through the water cycle, theyre ready to turn back into regular kids. But the magic key that will get them out of the cycle is locked in the school bathroom! The kids go through the town waterworks, and see how water is purified. Can they get to school through the bathroom pipes? Or are they stuck in the water cycle forever?

Clean-up!

Going Hands-On

Time: 30 minutes
Group Size: Four

During their trip through the waterworks, the Magic School Bus kids see how water gets cleaned up. Your kids can filter water to remove some natural impurities. Ahead of time mix water, pebbles, leaves, and soil together in jars.

What You Need

For each group:

• Small jar lids or soda-bottle caps
• Zip-lock baggies
• Masking tape
• Bowl of water
• Eyedropper

Talk About It

Ask children: What happens when water is heated? When is cools?

What To Do

1. Distribute materials and have kids place five to eight drops of water in lids. 
2. Carefully, they place lids into baggies and seal tightly.
3. Have students choose a window that gets plenty of sun (where kids can observe bags easily). Help them tape bags to the inside of the window.
4. Leave bags in the sun for most of the day. Near the end of the day, have the kids observe the bags. What do they see? (Much of the water should be gone from lid; top of the bag may look “cloudy” - that’s water vapor. You may also seee droplets on sides of bag.) Ask: What happened to the water? (evaporated)  

Next Stop

Ask students: What might have happened if we had left the baggies open? (Water would evaporate into the air in room.) Try it!

See The Cycle

Time: 15 minutes to prepare, then an overnight wait to observe
Group Size: Two or four

Your class may not be able to go through the water cycle, like Ms. Frizzle’s class, but with this activity they’ll see it in action! This activity works best when there is a big difference between day and night temperatures.

What You Need

For each group:

• 32-ounce mayonnaise jar
• 2 cups of water
• A strainer
• 1 cup of pebbles, leaves, and soil
• 2 bowls
• 3 coffee filters
• Spoon

Talk About It

Ask: What could you do to make muddy water clear?

What To Do

1. Let students examine the water mixture. Ask: How could you make this water clear? What would you use? 
2. Students hold strainers over bowls. Help them pour the water through strainers twice. 
3. As they work, have students observe the water. Ask: What is happening to the water? Why?
4. Help groups strain water through three coffee filters, using one filter at a time.
5. Have students observe water again. Ask: How does the water look? Why do you think that happened? Why do or don’t you think it’s clean enough to drink? 

Next Stop 

Ask students: What might be in clear water that we can’t see? How can we find out?