We built a new fire pit this summer, and shortly after we positioned the final brick we were lighting it up for the first of many summer bonfires. As much as we love sitting around the fire with friends and neighbors, we all know the real reason we have bonfires … s’mores! We ate up many bags of marshmallows this summer. Sure, they’re an inexpensive purchase, but did you know they’re easy to make at home?
Marshmallows are one of those foods we take for granted – they just appear in plastic bags in the store for our snacking pleasure! They’re kind of a mystery, aren’t they? Ask a kid what marshmallows are made of and how to make them, and you’re sure to get an entertaining answer!
Not only will they be the tastiest marshmallows you’ve ever eaten, you’ll walk away appreciating the math and science that go into one summer’s favorite treats!
I like the Vanilla Bean Marshmallow recipe from Annie’s Eats. There’s no shortage of marshmallow recipes on the web, though, so feel free to find one that suits your mood. You can come up with all kinds of crazy flavors! In fact, that’s a fun way to start out this project – if you could create any flavor of marshmallow in the world, what flavor would it be? Believe it or not, the first marshmallows were used as medicine. The root of the marshmallow plant produces a thick, glue-like substance that is actually soothing to the throat. The ancient Egyptians had a better idea, though, and mixed the dried root with honey to make the first marshmallow treats.
While the actual making of the marshmallows is best left to grownups (Hello, 240 degree boiling syrup!), this is a great opportunity to spend some time together in the kitchen as a family. Little ones can observe while you talk about what is going on in the pot.
Marshmallows are just a combination of sugar, water, and the stand-in for the marshmallow root: gelatin (which helps the marshmallows thicken and hold their shape). When you first start boiling the sugars and water together, it seems impossible that the clear, wet, goopy mess will ever transform into the fluffy white marshmallows we know and love! The sugar-water starts out as a solution. Boiling the sugar water changes it into a syrup. Water will boil at 212 degrees F. By adding sugar to the water, we change (raise) the boiling point of the solution. Use a candy or digital thermometer and allow the kids to watch how the solution changes as the temperature increases. At what temperature does the sugar syrup start to boil?
The real fun begins when you add the hot sugar syrup to the gelatin. Beating the syrup and gelatin together forms bubbles in mixture, and as the mixture cools the gelatin forms the glue that keeps the tiny air bubbles from collapsing. Watch in amazement as the mixture turns white and fluffy!
The hard part comes next – once you spread the marshmallows in the pan you have to wait at least 4 hours or up to overnight.
The recipe left us with some extra gelatin packets. While you’re waiting on the marshmallows, you can set up another fun activity using gelatin.
Once the marshmallows have set, they’re ready to cut. Now your little helpers can get in on the action and do a little math to boot! The marshmallows start out as a 9″x13″ rectangle, but the possibilities of marshmallow shapes are up to you!
If you’re sticking with squares, measure a graham cracker square and determine the best size of marshmallow square to cut. How many squares can you get out of your rectangle? A pizza cutter works perfectly for this.
For younger helpers, provide a variety of cookie cutters in different shapes and let them cut out marshmallows on their own, naming the shapes as they cut.
When the trees are bare and the snow starts to fall in just a few short months, you can do this squishy math all over again! You can’t have hot cocoa without marshmallows, right?! And if you’re looking for s’more math, be sure to check out this daily math problem!