If you find yourself at home with your children this vacation week, and you are looking for a kind of amazing, simple, fun and educational activity to do with them, you need look no further than your own kitchen. This activity – making a substance that has come to be called “oobleck”, in honor of the Dr. Seuss book “Bartholomew and the Oobleck” – will help your kids to practice scientific skills like observing, experimenting and problem solving (which are skills that will benefit your children in ALL facets of their lives). And as an added benefit, this is an activity that is actually a lot of fun for adults too. Really.
The cool thing about this substance is that it is most likely different from anything your child has encountered before. It is probably unlike anything YOU have encountered before. Oobleck is a fluid (like water, oil, shampoo…), but it behaves in ways that are different from most fluids. Describing it is difficult…you’ll just have to try it and see. But what makes this such a fun activity, and such a good science learning opportunity, is that oobleck seems to contradict the laws of physics. And this contradiction makes for GREAT science discovery. We call these experiences that defy children’s understanding “discrepant events” – moments that surprise kids because they don’t support, but rather challenge their views of the world. For very young children (3 and younger), a slotted spoon might provide a simple discrepant event. Children assume that all spoons hold water – but slotted spoons allow water to slip through them. Very young children will play for long periods with slotted spoons in water as they try to figure out what is happening. For older children, a more sophisticated event is needed to surprise them. Oobleck will challenge the assumptions of anyone from age 3 on up into adulthood. And it’s a LOT of fun to play with. Check out the activity below, which is adapted from Boston Children’s Museum’s Beyond the Chalkboard website (www.BeyondTheChalkboard.com).
You will need:
- A bowl
- 1 or 2 plates
- Spoons and other tools for scooping, measuring and investigating
- Newspaper or a tablecloth for the table
Pour about 1 cup of cornstarch into a bowl (no need to measure). Pour about ½ cup of water in with the cornstarch and then prepare to get messy – mix the cornstarch and water together with your hands (your child can do this if you’d like). What does it feel like to mix it up? You may notice that the mixture gets thicker the harder you stir. Mix the starch and water together gently until it’s all combined, pulling extra starch up from the bottom. Adjust the mixture by adding water or cornstarch – it should feel solid if you move your finger along the surface, but if you pick it up and hold it, it should drip through your fingers (weird, right?).
Now play! It is a good idea to cover your table with newspaper or a tablecloth – quality playing can get messy. Cornstarch cleans up easily with water, so it’s OK to get it on your clothes. Pour the oobleck on a plate. Scoop it up with a spoon. Hold it in your hands. Some questions to ask your child as you investigate this substance include: “What happens when you try to hold the oobleck? What happens if you squeeze it tight? What happens when you tap your finger on the surface of the oobleck? What else can you try?”
DO NOT POUR OOBLECK DOWN THE DRAIN!!! It can clog your sink. Instead, leave it out to dry then throw out the chunk of dried oobleck. You can also “remake” dried oobleck by adding water to it. If any oobleck spills on the table or on the floor, first pick up as much of it as you can and put it in a bowl or bucket to dry. Wipe up anything remaining with a sponge. You can also play with oobleck outside—it is a natural, biodegradable material, so it’s OK if it falls on the ground.
Want to read more about the science behind Oobleck? Try a search online for “non-newtonian fluids”. It’s pretty confusing (but also pretty amazing) stuff. And if you have it, maybe you can read the Dr. Seuss book “Bartholomew and the Oobleck” before or after you play. Most importantly, have fun!