There’s action! Adventure! Excitement! All inside Ralphie’s body. He’s sick and has to stay home from school. So Ms. Frizzle and the class take the Magic School Bus to Ralphie’s bedroom. They shrink, go inside his body, and travel in his bloodstream to his sore throat. The kids find out what’s making Ralphie sick, and see his white blood cells fight the bacteria in a raging battle. Ralphie’s winning! But there’s one problem. Now the white blood cells think the Magic School Bus is a germ. How can the class escape?
The Magic School Bus gets inside Ralphie’s body by going through a cut on his leg. Germs can get in the body that way, too. But usually the skin protects the body. Set up this activity to show how skin protects our bodies the way apple skin protects an apple.
- 2 sheets of paper
- 2 apples with no cuts or blemishes
- table knife
- copies of Skin to Germs: KEEP OUT!
As you set up the activity, ask: What do you think will happen to each apple in one week? |
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Label the sheets of paper A and B.
Wash hands and the apples. Place one apple on each sheet.
With the knife, peel back the skin to leave four openings about 1/2 inch in diameter on apple B.
Get an assistant with unwashed hands to rub her hands all around the apples.
Watch the apples for a week. Do not touch them. Each day, kids can write down their observations.
Ask kids: What is the purpose of the skin on an apple? How does the skin of an apple work like the skin of your body?
