Scavenge for Different Types of Chocolate
The most obvious option is to have participants collect various types of chocolate. White chocolate, milk chocolate and dark chocolate are some of the broadest categories; lesser-known types include sweet dark chocolate, semi-sweet chocolate and unsweetened chocolate. There is also a wide spectrum of dark chocolates based on percentage of cacao content. Although not all of these types taste the best right out of the wrapper (unsweetened chocolate is used only for baking), collecting them all will provide scavengers with some raw materials for further cooking and baking experiments.
Scavenge for Chocolate from Different Countries
Although the United States manufactures some of the most widely known brands of chocolate, such as Hershey's and Mars, many other countries are known for crafting cacao in their own signature styles. Many famous gourmet chocolates come from Belgium, France, Switzerland and Italy, each of which has its own distinct range of tastes. The breadth of the search can go on to include many different continents, giving participants an opportunity to taste styles of chocolate from different parts of the world, to see how they differ and what they have in common.
Scavenge Based on Additional Ingredients
This can be a particularly engaging option, since more and more chocolate makers are experimenting with unlikely ingredients to put in their chocolate bars. Even in many grocery stores you can find salted chocolate, chocolate with bacon and chocolate with hot peppers. Some of these items will be hard to find in the absence of specialty stores, so keep in mind your local resources before sending your hunters out for what may turn out to be a futile search.
Scavenge Based on the Label
If you're not committed to the educational potential of a chocolate scavenger hunt, you can focus on arbitrary but easily recognizable elements, like the details of a chocolate's labeling. Have your hunters find a chocolate bar with red lettering, one with a picture of a wild cat, one shaped in a circle, etc. Choosing this option will probably lead to some interesting surprises at the end of the hunt; participants may come home with their red-lettered chocolate bar to find that it's a type they've never tried before, and maybe never even knew existed.