Show your baby what the "depth" is.

Your little one is grown up enough to understand the concept of the "depth"!
You'll need:

• various bowls - a bucket, a bottle, a box, a cup, etc.
• small things - little toys, constructor detailes, spoons, lids, balls, etc.

Show the baby how to put the small things to the bowls, offer the little one repeat your actions.
Let your baby experimentalize with the bowls and things! He/she will surely like the activity, it will entertain your little explorer for a while.
Make photos of the process, upload to the App. Add some words about your baby impressions.