DIY Solar Oven

DIY: Solar Oven S’mores

DIY GeekMom

Our 10-year-old son, Sinister, has just finished his latest science project: to re-design a household item to be solar powered. So he designed his own solar oven. Not only did he embrace the full environmental element for this question, but he even figured out how to incorporate the most important ingredient of all: chocolate. All Hail, Sinister’s Solar S’mores!!

DIY Solar Oven


Now let me pre-empt by acknowledging there are dozens of ways to make your own solar oven (check out NASA). We have discussed this previously on GeekMom. However, I refused to show ANY of them to Sinister. I am one awful mother. Just ask my kids.

If you have never tried this at home with your own geeklings, then I strongly advise you let them just run with the idea. Find out how well they understand how an oven works and what they come up with themselves.

Here is Sinister’s report (his words, not mine):

Ingredients / Equipment

  • Square / Rectangle cardboard box
  • Glue and masking tape
  • Scissors
  • Stick (approx. 45cm)
  • Aluminium foil
  • Graham Crackers (or other digestive biscuits, depending on your local variety) – 2 per serve
  • Chocolate (we opted for Lindt, as it was thinner and easier to melt… plus, it’s on special this week)
  • Marshmallows – 1 per serve
  • Plate (for serving)


  1. Obtain a square / rectangle cardboard box
  2. Seal the box on all sides, using masking tape and glue
  3. Paint the box a dark color, like Black
  4. Cut a flap in the top of the box – choose a side with the most surface area for the most sunlight
  5. Line the box with Aluminium Foil (or whatever thin, shiny, metal roll of stuff you use in the kitchen) – glue it on and allow to dry
  6. Support the flap with a stick at a 45-degree angle
  7. Prepare the s’mores – take a Graham cracker, put a marshmallow on the cracker, and then a piece of chocolate on the marshmallow, and then another cracker on top
  8. Wrap the opening of the box with clear wrap to keep in the heat
  9. Put the box in the sunlight, with the open flap facing the sun
  10. Wait 15mins or until the chocolate and marshmallows have started to melt
  11. Enjoy your s’mores!


Results / Observations

  • It is really tricky to put in the al-foil and glue it. We could have lined it first and then sealed it up, but this would have caused problems when cutting the flap/hole
Lining the Solar Oven with tin foil
Photo by EG Mum
  • I painted it black to absorb more heat from outside to help with cooking
  • Allow plenty of time for paint to dry
  • By increasing the reflective surface area, we could increase the heat generated and cook even more! I thought a closed-in box would retain the heat better. An open oven could cook a closed-in item (like a pot) just as quickly.
  • I tried 2nd experiment without the plastic wrap over the top, and it worked just as well.

There you have it, folks! The assignment is due this Friday, and he should know results within a couple of weeks. Sinister is even taking the solar oven to school on Friday and cooking s’mores for his class.

*sniff, sniff* Bribing his teacher and class with chocolate. I’m so proud of him. This kid has real evil genius potential for global domination someday. Watch this space.

Do you have any suggestions for your own Solar Oven S’mores? Sinister is interested in any tips, advice, and reasons to cook s’mores again!

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