## Looks Can Be Deceiving

This game involves comparing differently shaped volumes. Humans are notoriously bad at judging volumes - a large beaker and a can of Pepsi can be the same volume, even though they often don't look it. To play this game, simply give kids bags full of various containers of a medium size. Then have groups pick two out at random, and guess which is bigger, describing the containers and writing down their answer on a piece of paper. Then they can use some water to find out for themselves (give them a jug full of it and something to catch drips).

This can be a fun activity or a competitive game. To make it into a game, each student in the group can receive a point if he guesses correctly. Groups should keep pulling out pairs of containers randomly until they have a sheet full of guesses and answers.

## Volume Data Race

For this game, give students a piece of cardstock with a series of 3D shape nets on it. The goal is for students to figure out the total volume of all the shapes added together. They must figure this out by cutting out the nets, folding them into 3D shapes (sticking them together with tape), measuring the sides of the shape, and calculating their volumes. After adding all their answers together, they can announce their number, and you can confirm if it is correct or incorrect. The winner is the first individual or group to come up with the correct answer.

For this activity, have students fill various containers with 1 cm blocks to figure out the volume, and then measure the container and calculate the volume using a formula. Are the numbers the same or different? To turn it into a challenge, have students complete as many comparisons as they can within a time limit. They can compete with each other, or try to beat their personal best.

## Largest Volume Competition

For this activity, give students a piece of cardstock of a particular size, and some tape, and have them compete to create a shape with the largest possible volume out of the card. To make it interesting, provide unusually shaped pieces of card (stars, circles, crosses etc.) Whoever is able to fit the most circular beads inside their shape wins. These can be compared using a measuring jug (to avoid having to count hundreds of beads).

When students need to learn formulas for calculating volume, help them along with a card matching game. Create two sets of index cards, one with drawings of 3D shapes, and another with equations to calculate the volume of those shapes. Mix them up randomly and then challenge students to match the cards into pairs within a time limit.