Children love to play with juice mixtures. Whether stirring up a frozen juice can with water, or mixing together several types of juice, it’s tasty, fun, and messy. Introduce math in the mix by pointing out ratios. I keep a whiteboard handy near the kitchen for when educational moments like this arise.
Suppose you get 50 limes in your food co-op like we did, and you wish to make limeade. Allow the children to experiment with various ratios of lime juice, water, and sugar or agave nectar.
Our limeade recipe: 1 part lime juice to 3 parts water with ⅓ cup of agave nectar. Mix and add ice.
This makes one quart of limeade. Yum! And oh so healthy!
To write this mathematically, use ratios. For the lime juice to water ratio, write 1:3. This means that if we are using a 1 cup measure, for every 1 cup of lime juice, we add 3 cups of water. For a larger batch, double both for a 2:6 ratio, which is mathematically equivalent to 1:3. Likewise we could triple it for 3:9 or quadruple it giving 4:12.
We might wonder what fraction of the whole mixture is straight lime juice. Looking at the 1:3 ratio shows us that there are 4 parts we are dealing with--1 part lime juice and 3 parts water. Since one of those parts is lime juice out of 4 parts total, we would say the mixture is ¼ lime juice. Likewise, it would contain ¾ water.
This mini-ratios kitchen lesson is a precursor to simplifying fractions. As we “play” math in the kitchen, we are providing our children with prior knowledge so that they will have a better understanding of math and story problems in school.
For teachers, a related middle school lesson on lemonade ratios and proportions is found in the Connected Math Comparing and Scaling Curriculum. Below is the link to the parent notes for the lesson. https://connectedmath.msu.edu/families/helping-with-math/cmp3-grade-7/7-4-comparing-and-scaling/