- 1/4 cup lemon juice
- cotton swab (per girl)
- sheet of paper (per girl)
- lamp with light bulb
- 1) Set the lemon juice where all the girls can reach
- 2) Have them write the name of another girl using a
cotton swab for a pen.
- 3) Let the messages dry. You will not be able to
read them when they are dry.
- 4) Turn on the lamp. After it has been on for a
while, have the girls sit in one group.
- 5) One by one, hold the papers close to the light
- 6) After the name is visible, have that girl try to
guess who wrote it.
Explanation: Different things
burn at different temperatures. The lemon juice chars at a lower temperature
than the paper, so when the writing is held near the lamp, the lemon juice
chars and becomes visible.
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