A box cake mix (or equivalent homemade cake mix) - white cake will take color best.
All ingredients listed on the back of the box. (ex. eggs, oil, water)
A mixing bowl
A hand mixer/egg beater (or you can mix by hand with a spoon)
Several bowls (one for each color!) - I suggest 4-6 bowls and colors for best result, but you can choose whatever you like!
Food dye 
Spoons to mix the dyed batter
1/4 cup measuring cup/spoon 
Cooking spray IF you plan to remove the cake from the jar or dish before serving. Not needed if serving in jars.
Mason jars, glass baking dish, or other glass oven-safe cookware to bake cakes in
*If you are baking in jars, you will also need a glass cake pan ready that all the jars can stand inside with water
# of mason jars advisement:
My suggestion is to use 8 of the 8 oz jars, 4 of the 16 oz jars, or you can even use the short 4 oz jars for a more bite-sized treat! You can also mix and match or use other oven safe glass.
An oven and oven mitts
Optional:
Cake frosting, sprinkles, candy corn (if you want a unicorn horn!), or any other cake toppings - have fun with it! Prepare your own toppings using your favorite recipe, or buy premade.

Please be advised that this class will require the use of an oven. Parent supervision is recommended for any students who are younger or inexperienced using the oven. 
Please be sure to check all ingredients you are using for allergens before using them for this class.