How to Make Oobleck and Explore Non-Newtonian Fluids with Kids

Learn to make oobleck at home and discover the fascinating science of non-Newtonian fluids through hands-on experiments.

1. What You'll Need. Gather these simple household items: 1 cup cornstarch, 1/2 cup water, food coloring (optional), mixing bowl, measuring cups, and newspaper or plastic tablecloth to protect surfaces. You might also want aprons or old clothes since oobleck can be messy. Having wet wipes nearby makes cleanup easier.
2. Making Your Oobleck. Start by pouring the cornstarch into your mixing bowl. Slowly add water while stirring with your hands or a spoon. The mixture will look lumpy at first, but keep mixing. Add water gradually until you reach the right consistency - it should flow like honey when you stir slowly but feel firm when you poke it quickly. If it's too thick, add a tiny bit more water. If it's too runny, sprinkle in more cornstarch. Add a few drops of food coloring if you want colored oobleck.
3. Understanding Non-Newtonian Fluids. Non-Newtonian fluids are materials that don't follow normal liquid rules. Regular liquids like water flow the same way whether you stir them fast or slow. But oobleck changes its behavior based on how much force you apply to it. When you move it gently, it flows like a liquid. When you hit it or squeeze it hard, it acts like a solid. This happens because the cornstarch particles jam together under pressure but flow freely when the pressure is gentle.
4. Fun Experiments to Try. Once your oobleck is ready, try these experiments: Punch the surface quickly with your fist - it should feel solid. Then slowly push your hand into it and watch it flow around your fingers like liquid. Try pouring it from one container to another, then immediately grabbing the stream mid-pour. Roll it into a ball in your hands, then stop moving and watch it melt through your fingers. You can also try walking on a large batch (if you step quickly and confidently) or see what happens when you put a vibrating object like a phone or speaker underneath it.
5. Real-World Connections. Help kids understand that oobleck isn't just a fun toy - similar materials exist in the real world. Ketchup is a non-Newtonian fluid that flows better when you shake the bottle. Silly Putty, paint, and even some body armor use similar properties. Scientists study these materials to create better products, from protective gear to special coatings. This simple kitchen experiment connects to real engineering and physics concepts.
6. Cleanup and Storage. Never pour oobleck down the drain as it can clog pipes. Instead, let it dry out completely and throw it in the trash, or dissolve it with lots of water before disposal. Wash hands thoroughly with soap and water. Any spills on clothing usually wash out with regular laundry detergent. You can store leftover oobleck in a covered container in the refrigerator for a few days, but you may need to add a little water to restore the right consistency.