Before the checks were signed, they realized something very simple. Bad apples sink and good apples float. All they had to do was dump all the apples into tanks of water and anything that sunk, they didn’t buy. This also solved the problem of hiding anything in the shipping containers.

Set up a sink or float experiment to teach toddlers and preschoolers about density and buoyancy. A simple sink or float activity is a great beginner science experiment that will introduce your toddlers and preschoolers to density and buoyancy.

Apples contain only the tiniest traces of fat, so there must be hidden gas inside them. This is why apples float and pears sink: The low gas content of the pear can’t compensate for the weight of the rest of the fruit, so down it goes.

Apples can float because 25% of their volume is air. If an item is more dense than water it will sink, it is less dense it will float. Apples are less dense than water, so they float!

When vegetables have molecules that are very close together, they are denser than water and they sink. When fruits and vegetables have molecules that are farther apart, they float because they are less dense than water.

Apples are made up of 25% air. Sure there is skin, seeds, and juices too, but there is enough air to make it float. If something is more dense than water it will sink, it is less dense it will float. Apples are less dense than water, so they float!

Explain to students that apples float because they are approximately 25% air (they have air pockets) which makes them less dense than water. I then have students draw what actually happened in the experiment and write what they learned.

Fresh apples consist of about 25% of air, and that’s enough to make them buoyant. The apples are less dense than water, and therefore they can float. For more educational apple activities, check out: Apple Oxidation Science Experiment

This is a simple experiment that students always enjoy doing. Pose the question – “Do you think an apple will sink or float in water?”. Allow students to hold and handle a few apples prior to making their predictions. You can make a class graph of students’ predictions or students can record their individual prediction on a page.

Stick a toothpick through the paper sail, one hole near the bottom, one hole on near the top. 6. Insert the toothpick sails into the apple pieces. 7. Place the apple boats into the water and see if they will float!