By Debby Venable

Oklahoma STEM Ambassador

Sometimes being able to include STEM activities into your afterschool program is easily accomplished by just considering your audience and the time of year that you want to study a particular subject.  Take Halloween for instance, it is the time of year that I love to study the human body and in particular, the skin and blood.  It is a great “hook” to get kids interested in science amidst the ghoulish backdrop of Halloween.

I would like to share two edible experiments that will have your students “engrossed” in body parts and begging for more.   The first experiment is studying the layers of the skin by creating an edible model of the skin. So much for just biting your fingernails, when you can eat the skin instead. 

Edible Model of Skin
What it teaches: The layers of skin
What to do: As a class, pour a layer of miniature marshmallows in a large, shallow dish. This will be the subcutaneous layer of the skin, which is made mostly from fat. Next, pour red-colored gelatin over the marshmallows. This will become the dermis, or inside layer of skin, which is full of blood vessels and nerve endings. After the gelatin has set, add a layer of fruit leather to serve as the epidermis, the protective, outer layer of skin. Add hair by cutting short pieces of black licorice strings and poking them into the fruit leather. (Tip: Poke a hole through the fruit leather first using a toothpick.) Add chocolate chips for moles or dehydrated strawberries for scabs. Yuck! (Or should that be “yum”?)

Another sure fire hit as you teach these units during Halloween time, is the study of the blood.  “I want to drink your blood” is uttered by every scary Halloween character for as long as I can remember.  I do remember being scared by these odd creatures and not thinking about how important our blood is to being alive. That is why my kids love studying about blood, not only how important it is to us, but also how some insects must have the blood of others to survive.  That is why I have included a recipe for drinkable blood that can be used to study a variety of subjects.  Still I like to use this around a Halloween theme.  Do with as you like…… it is still a “blood curling” experience.

Drinkable Blood
What it teaches: The color and consistency of human blood
What to do: After reading about ticks, leeches, lice, and other blood suckers, top off the unit with this concoction. Each student needs a plastic cup and a spoon. Have students pour 1/3 cup of water into the container. Next, add one teaspoon of chocolate syrup, three teaspoons of light corn syrup, and five to eight drops of red food coloring. Mix well. To add a little morbid fun, pour the “blood” into baggies and label with the students’ names and blood type and chill before drinking

Have an “engrossing” time as you study two components of the human body with a little spice of Halloween mixed in.