There are two different science activities that my daughter can’t get enough of. One is baking soda and vinegar, and the other is oil and water! This week’s Try It Tuesday activity is the result of an unexpected turn one of our oil, and water experiments took. Often times when trying activities with kids, crazy things happen. We accidentally added gravity to this simple oil and water activity, and the result was beautiful! We made a homemade lightbox, rubbed oil on a large serving tray, propped up one side of the tray, and squeezed colored water and baby oil onto the tray. It was so much fun to watch the colors snake down the tray, and react to the oil. This science activity offers multiple lessons at once. You can teach your children about gravity, and how oil and water react when mixed together at the same time. My favorite part about this activity is that my daughter doesn’t even know she is learning while she is having so much fun!
- Baby oil, or vegetable oil
- Food coloring, watered down tempera paint, or liquid watercolors
- Transfer pipettes (eye droppers/medicine droppers)
- Large clear serving tray, or a shallow storage container.
- Light table, or a homemade lightbox
- Cups, or containers for holding your colored water and oil.
Gather your materials.
Get your lightbox ready.
If you are lucky enough to have a light table, you can skip this step. You do not need a lightbox for this experiment, but the extra light makes it easier to see how the colors interact with the oil. For the lightbox, we used a large shallow 28-quart storage container. All you need to do is turn the storage container upside down, and place some sort of light source underneath the box. We use a small LED light with a clear mixing bowl covering it to tone down the brightness, but I have seen other people use a string of white Christmas lights.
Put a tablecloth, or shower curtain liner down on the floor.
If you are doing this activity inside, I would suggest you lay something on the ground. We lay a shower curtain liner on the ground in our dining room, and do this activity on the floor. It is a good thing we used a shower curtain liner too, because my daughter managed to knock over the cup of baby oil, and only one small drop got on the floor. All we had to do after we were done is throw the shower curtain liner in the washer for easy cleanup. I call that a mom win!
Prepare your colored water.
When we first started this experiment, we used food coloring and water. The second time around, we decided that we wanted to use neon colors. You can buy fluorescent colored liquid watercolors on Amazon for $30, or you can make your own. We used about a teaspoon of fluorescent tempera paint for each color and added very warm water to water it down. You will need to use warm enough water that your paint dissolves into the water when you stir it together. We like to use ice pop molds (like the ones pictured) when we do activities with colored water, because it saves time when setting up an activity, and cleaning up. I am very glad that we no longer have to search for several different small cups when we want to do activities like this. We put the colored water in the ice pop mold and filled a small cup with baby oil.
Oil your tray, container, or pan.
We used a large clear plastic serving tray. You can use any clear container that has edges to catch the oil and water. Pour oil onto your tray, and rub it all around with a paper towel.
Prop your tray up on one side.
You want to prop your tray up on one side so that gravity can do it’s job when you add the oil and water. The first time we did this activity, the plug to the light was so thick that it lifted the bucket up, and tilted our tray. That’s how we found out how much better this activity is when you tilt the tray. Before, it was just dripping colored water onto a flat tray. It is ten times better when you prop the tray up. You can use a folded paper towel wedged under the edge of the tray for a little bit of motion, or you can speed up the action by using something bigger, like an upside down plastic cereal bowl under the edge of the tray.
- Place plastic transfer pipettes into your colored water, and baby oil. We like to use plastic pipettes we found on Amazon, but you can use eye droppers or medicine droppers.
Turn on the light under your lightbox, and have fun dripping the colored water and oil onto your tray!
It’s fun to watch the colored water snake into the puddle of oil and water on the lower edge of the tray. If you only add a little bit of oil, you can see the colors swirl together. If you add more oil, the colored water takes longer to break through the oil barrier and join the puddle of colored water that has already formed. Note these pictures are dark because of how bright the light under the light box was. We did not turn the lights off for this activity!
This is such a fun activity for demonstrating gravity, and the reaction that oil and water have when mixed together. I hope you are inspired to let your little ones play with oil and water sometime soon. You don’t need to be intimidated by not having the right materials, and you don’t have to spend a lot of money, just use what you have! Go dig in your medicine cabinet for some old medicine droppers, dig in your cupboard for some vegetable oil, and pick up some food coloring next time you go grocery shopping if you don’t already have some on hand. If you loved this activity, be sure to pin it for later, and don’t forget to check back next week to see what activity we try out next!