Who are the Hippie Pandas? Four girls from Rochester, ages 11-14 who have created a solar pasteurizer for use in Nicaragua, where raw milk consumption causes illness and miscarriage in pregnant women. Their project was such a success that it's already been implemented:

Using common materials, they came up with a solution for the pasteurization problem. Laying aluminum foil over a piece of cardboard or woven mat, a reflector is made. A receptacle is painted black to absorb heat and filled with unpasteurized milk.

Initially the girls used a thermometer to monitor when the temperature reached an acceptable temperature but, realizing thermometers might be tough to come by in Nicaragua, they came up with an alternative solution: bee’s wax. If using a thermometer, the milk is pasteurized after 30 minutes at 145 degrees or when the bee’s wax is fully melted.

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