• Chocolate originally comes from a tropical tree known as Theobroma cacao.chocolate bar image by terex from Fotolia.com
  
  Get your students' attention when it's time for science by performing experiments and activities centered on chocolate. From its low melting temperature to the complexities of the ingredients that make up chocolate as we know it today, children can learn more about the sweet science of chocolate and can also have a tasty treat at the end of the lesson.
  
  

Glossy Chocolate

• Glossy surfaces on the chocolate are highly prized by candy makers, so students can experiment with up to six brands of chocolate to see which one produces the glossiest surface. With adult supervision, students can melt the brands of chocolate and form handmade molded candies. Candies are then photographed for evaluation and tested with a reflective spot meter--a hand-held meter or device built into some cameras that measures the light reflected from a spot in a scene.
  
  Students can rank the chocolate candies in order of glossiest and least glossy and compare the rankings to the price of the chocolate to see if the most expensive chocolates are truly the "best" for candy making.
  
  

Melting Chocolate

• In a lesson unit on temperatures, students can determine at what temperature chocolate will melt. The experiment uses six chocolate bars that are the same size and shape, divided onto six paper plates. Students place one plate outside in the shade, one in the sun, one in a car and the rest in other interesting locations. They then use a thermometer to record the temperatures at each location. After 10 minutes in each location, students evaluate the chocolate bars to see what melting has occurred and compare that to the temperatures recorded.
  
  

Chocolate Turning White

• When sugar and fat separate from each other in a chocolate bar, the normally brown chocolate gets whitish scales and patches on it. Manufacturers try to avoid letting the chocolate turn white, so children can experiment on what it takes for chocolate to turn white and what's the fastest way to do so.
  
  The experiment uses four pieces of natural chocolate, each piece set in a dish. Students put one piece in a humid environment and one in a cool environment. With adult supervision, students can melt one piece on a stove, and the last one can be placed in a constant or neutral environment.
  
  Once the chocolate has been melted on the stove, students pour it back into the dish and let it harden again. The students can then evaluate which chocolate dish turns white first, and they can draw conclusions about what conditions make chocolate turn white.