intro:
Dive into measurement and help children develop an understanding of depth perception. This fun activity will help the children explore depths of substances in different containers.

set up ideas:
Prepare for clean up before you start this activity so that you can avoid a mess. If you use sand, make sure you have a vacuum handy. If you are using snow, make sure you have towels or a mop on hand for when it melts.

let's get started

Gather connecting cubes and a container with 6-12 inches of sand or snow. Make sure you’ve got your clean-up supplies as well! Ask your students what they know about depth perception. If they don’t understand, tell them how the activity will help them develop an understanding.

step 1
Fill the container with sand or snow so that the substance is at least six inches deep. Have the children estimate how many cubes deep the sand or snow is before they measure.
step 2
Have the children use the three connecting cubes to measure the depth of the sand.
step 3
The children will record how many cubes it takes to go all the way to the bottom of the container and while the cubes still stick out at the top.
step 4
Adjust the levels of the substance in the container so that the depth changes.

Ask how their estimates varied from their results and ask why they think different people had different estimates. Open the conversation to discuss perspective. While a box of sand may seem like it’s one depth, it may be much deeper. Discuss how perception varies from person to person.
Tips and Tricks
Try mixing materials to see what sort of effect this has on the activity. Try with a liquid or less viscous material. This could help your students understand that different consistencies appear to have different depths.
Follow up Activity
Try to use different materials, such as marbles or beads. The varied texture may challenge children when it comes to estimating the depth of these materials. This makes the activity a bit more complex, as it furthers the discussion of perception and optical illusions.