Special Features

Printable Version for your convenience!

Julianne Vrooman

Caroline Samoska

Name of Activity: The Put - in - Order Problem

Topic: Geometry, Spatial Reasoning

Grade Level: 3 - 4

Materials Needed: One set of toothpick cards (per group)

Four toothpicks (per group, or per student)

Description of Activity:

Introduce the activity by arranging four toothpicks on the overhead in a square. Ask the class what other shapes could they make by moving just one toothpick (flip top of square up to form the letter "J" as an example). Explain that the only rule is that the toothpicks must all be touching, somehow, at all times. Let the students come up with suggestions, and demonstrate how the shape can change so much by just moving one piece.

Divide the students into groups. Instruct the students to select one card from the pile of "toothpick" cards they have on their table. After they have selected this card, tell them to move one toothpick, and the find the matching card in the stack and place it next to the original card. Continue like this until all of the cards are lined in a row, making sure that each pattern can be made from the previous design by moving just one toothpick. Have the students use the numbers on the card to record how they solved the problem by listing the numbers in order. Continue doing this until they have at least three ways to arrange the cards. Each group will then share one of their solutions with the rest of the class.

**EXTRA** Have the students try to make a continuous loop of the cards so each changes to the one on either side if one toothpick is moved.