This lesson introduces two new constructions, each of which uses an angle-fold in combination with a parallel-fold. In the Peek-a-boo, the motion of the angle-fold is hidden by the parallel-fold, so it appears to “come from nowhere.” The Hand-waver uses a series connection to move the angle-fold so the action is on the side of the page, not along the gutter. These two constructions are the basis for many of the pop-ups in commercial cards and books.
For the class:
Pop-up books that use the "Peek-a-boo" or "Hand-waver" constructions
For each student:
Scissors, tape, rulers, ballpoint pen, and Post-it™
Outcome: Each construction uses both a parallel-fold and an angle-fold. In the Peek-a-boo, the two pop-ups are in parallel, while in the Hand-waver the angle-fold is in series with the parallel-fold. As a result, the Peek-a-boo produces up-and-down motion along the gutter, while the Hand-waver uses the parallel-fold to move the motion to the middle of the page.
4. Finding hand-wavers and peek-a-boos. Provide commercially made pop-up books that have these constructions. Students should look through these books to see how professional paper engineers have used the same consteructions they have just made. 5. Extensions. Here are some experiments and design challenges: