Fun STEAM Activity! Practice Serial Dilutions With Breakfast Cereal

Science can be a ton of fun, and this STEAM activity proves it. This edible math and science project encourages kids to play with their food. Measuring breakfast cereal and milk, or food coloring and water, lets young learners experiment with serial dilutions, a technique used by scientists in real-life labs everywhere. (Kids who enjoy this experiment might also like The Magic School Bus Microscope Lab.)

You’ll Need

• Clear or white cups or bowls
• Breakfast cereal
• Spoon
• Milk
• Water
• Food coloring
• Measuring spoons
• Measuring cups

Safety Tips and Hints: This is a great project to do at snack time, because you can eat the first part of the experiment!

What to Do

Step 1: Let your child measure ½ cup milk into each of 5 cups. Line the cups up in a row.

Step 2: Have your child add ¼ cup cereal to the first cup.

Step 3: Ask him to stir the cereal and milk with a spoon. Let him remove 1 tsp of the cereal/milk mixture and put it into the next cup of milk.

Step 4: Stir the mixture in the new cup, remove another teaspoon, and move it to the next cup of milk. Encourage your child to try to scoop random samples from the cups so that she doesn't get all of the floating cereal in the spoon! Repeat until she's added a spoonful of cereal/milk to each cup, in order.

Step 5: Observe cereal in the cups. Ask your child to count how many pieces of cereal are in each cup. Ask him whether it’s easier to count the number of pieces of cereal in the last cup than in the cup that he added cereal to first. 

Step 7: This time, ask him to measure 250 ml (1 cup) water into each cup, and line them up as before.

Step 8: Let your child add several drops of food coloring to the first cup and stir.

Step 10: To make a 1 to 100 dilution, let your child take 5 tsp colored water from the second cup and put it in the 3^rd cup and so on.

Step 11: Repeat, until she has diluted colored water into all the cups. The color should appear lighter and lighter with each dilution.

Step 12: Ask your child to compare the color in the cups. Congratulate him — he's made a series of serial dilutions: 

• Cup #1 - undiluted
• Cup #2 - 1 to 10 dilution
• Cup #3 - 1 to 100 dilution
• Cup #4 - 1 to 1000 dilution
• Cup #5 - 1 to 10,000 dilution

Creative Enrichment

Instead of adding plain water to the cups, add water containing yellow food coloring to each cup. Do serial dilutions with another color, like blue, to test how color mixing works with different dilutions. Try it with other colors.

The STEAM Behind the Fun

Serial dilutions are often used by scientists to quickly and accurately lower the concentration of a liquid. (Concentration refers to how many pieces of a certain substance are contained in a certain amount of something, like liquid or air.) 

In this science/math activity, you do serial dilutions using breakfast cereal! Each time you dilute the milk/cereal mixture, you end up with fewer and fewer pieces of cereal in the cups, lowering the cereal concentration in each ½ cup of milk as you go.

Imagine that you’re a scientist testing some water from a well to get an exact count of how many bacteria are in a sample of the water. Too many bacteria in a single sample are impossible to count, like the cereal in the first cup. However, making serial dilutions of the well water make it so that the bacteria can be easily counted, like the cereal in the last cup. Using multiplication, it’s now possible to calculate how many bacteria were in the original sample. 

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This project and more like it are featured in Liz’s new book STEAM Lab for Kids: 52 Creative Hands-On Projects Using Science, Technology, Engineering, Art and Math (Quarry Books, spring 2018).

© Quarry Books, 2018/STEAM Lab for Kids; Photos: © Quarry Books