Use tinfoil to make a river and set it up on a slight slope.

You might want to do this activity outside, but if you do it inside, set it up in a large tupperware container or baking dish.

Collect some materials you can use to build a dam. You can use natural materials that you find outside, or man-made materials you have around the house.

You can make a boat using acorns, toothpicks and paper like in the picture.

You can also use an item that you have around the house that floats like a rubber duck.

Use the materials you collected and start building your dam.

Test your dam by pouring water down your river.

This activity will take trial and error as you test your dam to see if it holds enough water to float your object.

Try to problem solve to fix any problems you have with your dam.

You might need to use some materials like playdough or mud to plug the holes.