Marshmallow Toothpick Tower Challenge

What you need

• Plate or tray, 1 tray to build on (optional)
• Phone, For a timer and photos (optional)
• Mini marshmallows, a big pile
• Toothpicks, a big pile

How to do it

Grown-up prep: Put a pile of mini marshmallows and a pile of toothpicks on a plate or tray. Stay close while kids build, because toothpick points are sharp. Show younger builders how to hold toothpicks by the middle and poke away from fingers. Mini marshmallows can be a choking hazard, so keep them away from toddlers and babies nearby. Keep a few clean marshmallows aside for a snack at the end.

1. Put marshmallows and toothpicks in two piles on your tray, saving some for snacking.
2. Poke three toothpicks into three marshmallows to make a triangle.
3. Now use four toothpicks and four marshmallows to make a square.
4. Gently push on one corner of the square, then the triangle. Watch!
   Ask: Which shape squished sideways, and which one stayed the same?
5. Build a short tower section with squares, and another with triangles.
6. Now build the tallest tower you can, using the shapes you think work best. Ask for help if you need it
7. Ten-second test! Let go of the tower and count to ten.
   Ask: Did it stand on its own? If it fell, where did it break first?
8. Measure or photo your tower, fix weak spots, then try to beat your record.
9. Now show your friends, or build more! How tall can your next tower get?
   Ask: Who will you challenge to beat your tower, and what will you tell them about triangles?

Play it again

• Stick limit: you only get 30 toothpicks, so build the tallest tower that passes the ten-second test.
• Top hat: build a tower strong enough to hold a small toy on top.
• Bridge builder: build a bridge between two books that can stand on its own.