Balancing Forks on a Toothpick

1. Balancing Forks on a Toothpick Materials: 2 forks; toothpick; cup What you do: Interlock forks around toothpick and balance on cup rim. What students see: Heavy forks hang far off the side without falling. Question: Where is the balance point hiding? 2. Interleaved Books Won't Pull Apart Materials: 2 paperback books/catalogs What you do: Interleave pages, then try pulling books apart. What students see: Loose pages become incredibly hard to separate. Question: How can paper hold this strongly with no glue? 3. Pendulum Return-Point Challenge Materials: Heavy soft ball or large washer securely attached to a long string; floor tape or a marked release point What you do: Release the pendulum from a clearly marked point beside the teacher's outstretched hand—never from a face—and do not push it. What students see: It swings back toward the starting point but does not return higher. Question: Why doesn't it come back higher than where it started? Safety: Teacher-only setup and release; keep every student outside the swing path.

Predict → observe three demonstrations → compare what changed → choose independent activity station → cleanup/share. Guiding questions: Question: Where is the balance point hiding? Question: How can paper hold this strongly with no glue? Question: Why doesn't it come back higher than where it started?