What you need
Flat toothpicks, copies of tricky toothpick puzzles
What to do
- Make some triangles and squares with the toothpicks.
- Make other shapes if you want.
- Now try some of the Tricky Toothpick Puzzles.
What to ask
- How many triangles or squares are left each time you change or move a toothpick?
- How many of the shapes are exactly alike (congruent)? How do you know?
- Which shapes are similar (look alike but may be different sizes)?
- What is the smallest number of toothpicks you need to make 3 squares? 2 squares? 4 squares?
What’s next?
- Make up you own toothpick puzzle for someone else to solve!
- Search for shapes around the house that are similar (same shape) or congruent (same shape and size).