S'More or S'Less Heat?

Challenge
Did you know in August there are two separate special days dedicated to marshmallows? One day is August 10, which is National S’mores Day, and you can’t have a s’more without a marshmallow! The other day is August 30, which is Toasted Marshmallow Day! So of course, this month’s challenge has to do with marshmallows, especially toasting them AND making s’mores! Your challenge is to create a contraption that will make a marshmallow warm and soft along with chocolate to make a s’mores. You probably will not be able to really toast it since fire will not be used. You’ll be using the sun’s heat energy to help you accomplish the task. What materials will work best to capture the heat?  How large should the contraption be?  What shape, size, and design should it be to be most effective? How can you measure the effectiveness of the contraption?

Your contraption and creation do have some criteria and constraints. Each contraption or solar oven should test one marshmallow or piece of chocolate at a time. All the marshmallows and chocolate should be about the same size and type. While testing, the solar ovens should be placed in the same sunny area. Use the same thermometer for taking the temperature inside the box.

Materials

• aluminum foil
• carboard boxes
• clear material (plastic wrap, transparencies, etc.)
• felt or other fabric
• containers/plates for setting food items
• shiny paper
• rocks
• mirrors
• tape
• marshmallows
• graham crackers
• chocolate bars
• thermometer
• stopwatch
• any other items needed

Hints and Tips for Success

1. Allow students planning and discussion time by having them experiment with the items to see how flexible, movable, and heavy they are. Also, let students experiment for how hot objects get under light or outside.
2. After experimenting, allow student groups to plan their design by drawing it out and labeling their materials being used. Include as many ways to improve their ovens as needed. You may want to help students with a design by suggesting a window on top of their ovens to be able to see what’s happening inside.
3. For differentiation, adjust the amount of materials available and allowed to use, add any additional materials, take away certain materials, show them different solar oven examples, extend/lessen the time of cooking, try different sizes of marshmallows or chocolate. Adjustments could be made to make it more challenging or simpler.
4. Make sure to standardize the dimensions of the marshmallow or chocolate. Remind students to take heat measurements with the thermometers periodically throughout “toasting” the marshmallows.

Connect to science by discussing heat energy, properties of materials which work best for the solar oven, energy transformations, solar