“A Glass Half Full” Science Experiment

With so many material things available to our children, it is sometimes difficult for them to appreciate all that they have; some days their blessings can feel like nothing!  This simple experiment will give them a choice: When they look at a glass half-filled with water they can see a glass half full, or they can see a glass half empty.


• Plastic water bottle• Knife• Water


All of us are exposed to a ton of advertising that encourages us to want more and more “things” we don’t need in our lives while neglecting to teach us to appreciate things like God’s love and the eternal life that awaits God’s children in heaven. We can learn to be grateful for all the blessings God has given us without giving in to the temptation to want more and more treasures on earth. This experiment can show us how:


• Fill the bottle with water.• Use the sharp end of the knife to make a small hole in the bottle (only older children should use the knife).• Note how slowly water drips out of a little hole.• Now make a second, larger hole in the bottle higher up, and see how the water will rush out.


When a second hole is punched in the bottle, it allows air to rush in while water is rushing out. Since water is denser than air, the water will rush out the hole that is lowest until there is no longer water at that level. Then we will have created mass-density equalization between the air and the water.


Think of yourselves as water bottles. Think of the holes in the water bottles as temptations. One little hole in a bottle might be cheating on a test or taking money from our parents without telling them. Two holes in the bottle will allow the water to rush out. Two holes is like giving in to that extra temptation after the first one seemed to go well! Before we know it, we’re “spiritually empty!” We want to give our ALL to Jesus. Let’s remember not to give in to multiple temptations to do wrong—let’s not even give in to one! Did you enjoy this experiment?  Let us know!

The above post was written by guest blogger, Mary Kate Warner. For questions about this activity, please reach out to her personally at Christianity Cove.