What You Need

• Whipping cream
• Small jar (baby food jars work best)

How to Do this Activity

Start by helping your child pour a small amount of cream into a jar. Be sure to start small, because the more cream you add, the more your child will have to shake. Ask your child what the cream looks like before you get started — “Is it liquid or solid?”

Seal the jar tightly and have her shake it (you might need to help at first). Be sure to supervise, and, if you’re using a glass (breakable) jar, remind your child to be careful not to drop it or let it go.

After several minutes of serious shaking, a clump of butter should form. Give your child time to talk and ask about how the substance changed. Pour the liquid (whey) out and chill the butter.

Then, if your child wants to mold the butter into shapes, work together to spread it on a piece of waxed paper and put it in the freezer to get even colder. Once it’s a bit harder, take it out and lay the waxed paper on the table. Have your child press decorations into it or use cookie cutters to make shapes!

What Your Child Learns

Through this activity, your child begins to understand the concept of properties of matter — that a liquid can become a solid. Your child will observe, ask questions, and perhaps make a hypothesis about why the cream turned to butter. These "I wonder" moments form the beginning of scientific thinking.