A great themed study that can cover cross curriculum studies is creating maps or landforms that are edible. Students will enjoy the opportunity to create something and have fun trying it. One of my favorites is creating an edible landfill. Most students have little experience with landfills, and this lesson provides a detailed description (with treats) of what different layers in the landfill perform and the reasons why. This can be done individually with small bowls, or in a large pan, then separated for each student.
Plastic bowl (hole in ground) Marshmallows (fabric layer)
Fruit Roll-ups (liners & cap) Chocolate Pudding (dirt)
Licorice (leachate collection) Green sprinkles (grass)
M&Ms, animal crackers (garbage) Smarties (pea gravel)
Sugar wafers (drainage layer) Spoons
Step one is to line a bowl with fruit-roll up. This is the liner of the landfill. Liners seal garbage and leachate (any liquids) in the landfill.
Cover the fruit roll-up with a layer of sugar wafers, which is your drainage area. This layer collects any liquid passing through the leachate collection pipes. Leachate is pumped to a treatment plant.
Add a layer of marshmallows, which acts as a fabric layer, that cushions the bottom layers from punctures.
Sprinkle some of the Smarties (pea gravel) over the marshmallows. Pea gravel filters liquid into collection pipes for treatment.
Tear licorice (leachate collection pipes) in pieces the length of the bowl and lay in rows over Smarties. Leachate collection pipes collect liquid and pump it to a treatment plant.
Add remaining Smarties on top of licorice.
Place another layer of marshmallows over the Smarties. This layer cushions the layers below from any sharp objects that may be contained in the garbage.
Dump a layer of crushed animal crackers (or Oreos) and M&Ms over the marshmallows. This layer represents assorted garbage.
Cover with a thin layer of pudding. Each night, the garbage in a landfill is covered with a layer of material (usually top soil). This layer reduces odors and litter problems.
Alternate crackers and M&Ms with pudding (or crumbs) until layers are 1/2" from the top of the fruit roll-up (approximate).
Top it off with pudding (or crumbs).
Sprinkle another layer of marshmallows over the pudding. This fabric layer protects the top layers from sharp objects in the garbage below.
Unroll another fruit roll-up and place on top for the cap. A cap protects the landfill from rain water. This reduces the amount of liquid entering the landfill and flowing into the leachate collection pipes.
Add a final layer of pudding (or crumbs) and top off with candy sprinkles for grass.
This lesson can include additional lessons with children on how to recycle more. The class might start a project for recycling in their community, or start to learn how to compost material to protect landfills from overcrowding.
This lesson might also spark interest with some students about how other countries handle their garbage, whether in a landfill or in some other fashion and the impact that population has on distribution of trash.
Students will really have an understanding of how landfills work once they complete this fun, edible project.