Looking for an easy STEM activity the whole family can enjoy? This DIY solar s’mores oven lets kids explore science, engineering, and renewable energy using everyday household materials. As you build and test your oven together, you can make predictions, observe how sunlight creates heat, and finish the experiment with a tasty s’more!
This article is presented by Reach Cyber Charter School.
Hands-on STEM learning starts early at Reach Cyber Charter School. This simple solar oven project gives families a fun way to explore science together at home—just one example of the curiosity-driven learning Reach encourages every day.
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☀️ Solar Oven Activity at a Glance
Build time: About 20–30 minutes
Heating time: Approximately 20–60 minutes, depending on the weather
Best time to try it: Between 11 a.m. and 2 p.m. on a sunny day
Adult help: Recommended, especially when cutting the cardboard
How Does a Solar Oven Work?
A solar oven uses sunlight as its heat source. The aluminum foil reflects sunlight into the box, while the black construction paper absorbs the sun’s energy and helps create heat. Plastic wrap traps warm air inside the box, similar to the way a greenhouse holds heat.
As you build your oven, encourage kids to think like scientists: Make a prediction, test the oven, observe what happens, and consider what could make it work even better.
Gather your supplies
Besides the ingredients for your s'mores, you'll need for the solar oven:
- One clean, shallow cardboard box
- Several sheets of black construction paper
- Aluminum foil
- Plastic wrap
- Tape
- Scissors
- A stick, wooden dowel rod, or ruler
- Optional: Pencil, marker, and newspaper
How to Build a Solar S’mores Oven
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Step 1: Make the Oven Door
Draw a flap on the top of the cardboard box, leaving about a 1-inch border around the edges. Cut along three sides of the flap, leaving the back attached so it acts as a hinge.
Cut a piece of aluminum foil that is approximately the same size as the flap. Tape the foil to the underside of the flap with the shiny side facing outward.
⭐ Pro Tip: Keep the aluminum foil as smooth and wrinkle-free as possible. A smooth surface will reflect sunlight into the oven more effectively.
Step 2: Line the Inside of the Oven
Cover the bottom of the box with black construction paper and secure it with tape. The black paper will absorb energy from the sun and help heat the inside of the oven.
For extra insulation, roll sheets of newspaper into tubes and place them around the inside edges of the box.
⭐ Extra Tip: Insulation helps slow the loss of heat. Ask your child why newspaper might help keep the inside of the oven warmer.
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Step 3: Add the Plastic Window
Cut a piece of plastic wrap slightly larger than the opening created by the flap. Stretch the plastic wrap tightly across the opening on the underside of the box lid and secure all four sides with tape.
Try to seal the edges as tightly as possible. The plastic wrap will help trap warm air inside the oven.
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Step 4: Prepare the S’mores
Place graham crackers inside the oven and top them with chocolate and marshmallows. You can add the top graham cracker after the chocolate and marshmallow have warmed.
Arrange the s’mores on the black paper, then close the box lid.
Step 5: Use Your Solar Oven
Place the oven in a sunny outdoor location, preferably between 11 a.m. and 2 p.m., when the sun is typically strongest.
Lift the foil-covered flap and use a ruler, stick, or wooden dowel rod to hold it open. Adjust the flap so the aluminum foil reflects sunlight through the plastic-covered opening and into the box.
Watch your s’mores closely and observe how they change. Heating time will vary depending on the amount of sunlight, outdoor temperature, wind, and design of the oven.
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Prefer a printable version? Follow along with the official Solar S'mores Oven Activity Guide while you build together. 👉 Open the Solar S’mores Oven Activity Guide
Solar Oven STEM Questions for Kids
Extend the learning by asking questions before, during, and after the experiment:
- What do you think is the purpose of the aluminum foil?
- Why do you think the bottom of the oven is covered with black paper?
- How does the plastic wrap help the oven become warmer?
- How long do you predict it will take for the marshmallow to soften?
- What changes do you notice as the s’more heats?
- How could you change the design to make the oven warmer?
- What do you think would happen on a cloudy or windy day?
- Have you noticed solar panels in your community?
- How do solar panels help provide energy for homes and buildings?
Explore STEM Learning With Reach Cyber Charter School
Reach Cyber Charter School values each student’s creativity, ability, and passion for learning. Its integrated STEM and Career Readiness curriculum allows students to explore their interests and prepare for the future.
These experiences begin in elementary school with STEM courses and career readiness kits that encourage students to create, investigate, solve problems, and discover new possibilities.
Visit a Reach Cyber Charter School information session to learn more about its programming. Dates, times, and registration information are available online.
