Solar Oven S’mores

In South Texas, we get plenty of sunshine in the summer.  We get so much sun that you can even cook food in a solar oven. Pandemic parenting means working with what you’ve got, right? So, on this summer solstice, we are sharing tips for building a DIY solar oven to make s’mores, plus links to more ambitious recipes. This is also an opportunity to talk with your kids about the science of the sun.

For more ideas about summer experiences you can do while learning at home with your kids, visit the main page, Charter a Summer of Learning.

Build a Cardboard Solar Oven

Our team found a great how-to guide for building a solar oven out of cardboard, foil, construction paper, and plastic wrap. We also used heavy duty scissors and duct tape. My daughter picked a cardboard box from the recycling bin and cut some of the flaps off. She lined the lid with foil and the inside of the box with black construction paper. We used stretch wrap to cover the box, but you could also use cling wrap from your kitchen.

Making S’mores in a Solar Oven

The ingredients for s’mores are graham crackers, milk chocolate bars, and marshmallows. My daughter broke the graham crackers in half and spread them out in the bottom of the oven. She topped each one with a square of chocolate and a big marshmallow. Then, we used the stretch wrap to make a clear cover over the box.

We set the box out on a sunny patio in the afternoon. After about 45 minutes, the chocolate had melted, and the marshmallows looked puffier. We waited another hour until the marshmallows had deformed and rolled over.

Peeling back the stretch wrap, the air inside the oven felt really hot—like a car that’s been parked in the sun. This type of solar oven won’t caramelize marshmallows like a campfire, but it won’t burn them, and it makes them deliciously soft. We topped each s’more with another half graham cracker and smooshed. Delicious!

Sun Science

Cooking s’mores in a solar oven is a great opportunity to talk with your kids about the science of the sun. Isn’t it amazing that the sun’s rays are hot enough to cook food?

If you’re wondering what students are expected to know about the sun, look up the science TEKS for elementary and middle school. You can start a discussion with your kids about these concepts:

The location of the sun and the earth in our solar system. Noticing how the sun rises and sets, and what time of day is best to use the solar oven.

The earth is tilted on its axis, and that influences the seasons in temperate zones. This is especially timely if you make s’mores on the summer solstice.

The energy of the sun’s rays comes from a fusion reaction in a yellow star. That radiation travels across space, and through our atmosphere, and provides the energy for life on earth.

The solar oven functions like a greenhouse, and that could spark a discussion about human-caused climate change.

Advanced Recipes and Ovens

We also attempted to build a bigger solar oven and bake potatoes in it. However, our attempts failed—partly because of weather (passing clouds and showers) and partly because of design flaws. Failure is part of science; the important thing is to try again. Tinkering with the design is part of the fun of building projects. I shared a work-in-progress photo on a group text with twenty of my brainy cousins, and they were full of interesting suggestions like spiking the potatoes with nails, wrapping them in foil, or placing them on a dark cast iron pan.

Obviously there are easier ways to cook potatoes, but that’s not the point. We are stuck at home with potatoes, cardboard, foil, plexiglass, etc. in another scorching Texas summer, and we want to have some fun.

Here are some how to guides and recipes to inspire you to build a more advanced solar oven:

“How to Make and Use a Solar Oven,” WikiHow, May 22, 2020

“Make a Solar Oven From Cardboard Box in 5 Steps,” Mila Luleva, Green Optimistic, February 12, 2015

“Solar Cooking: Baked Potatoes”, Texas Homesteader

“Sensational Solar Baked Potatoes,” Sun Oven, December 2, 2013

After the rain shower, I cheated and finished baking the potato in our kitchen. It was delicious! I will try again to bake a potato in a solar oven from start to finish.

Read More About Solar Ovens

“DIY Solar Oven Smores,” Karen, Desert Chica, May 25, 2018

“Make S’mores With a Solar Oven!” NASA Climate Kids

“How To Make a Solar Oven,” Home Science Tools

“How Solar Cooking Works,” Julia Layton, How Stuff Works

“Cook With the Sun: Solar Oven Recipes,” Mary Mazzoni, Earth911, July 2, 2019

“6 Beginner Recipes for Solar Ovens,” Robin Jacobs, EarthEasy, June 20, 2014

For more ideas about summer experiences you can do while learning at home with your kids, visit the main page, Charter a Summer of Learning.

About the Author

Inga Cotton is the Founder and Executive Director of San Antonio Charter Moms. Ever since her kids were babies, she has been spouting off random facts, hoping that some of it would stick. Her kids do like to eat s’mores, but insist on washing their hands immediately afterwards.