Create edible slime

What can we use instead of cornstarch if we don't have any?

You can substitute powdered sugar or tapioca starch in equal amounts while following the step to add cornstarch 1 tablespoon at a time, but expect a sweeter or slightly chewier slime and adjust the amount until the mixture pulls away from the bowl.

What should we do if the marshmallows don't melt smoothly or the slime stays too sticky?

Ask an adult to heat the bowl in the microwave in 5–10 second increments until the marshmallows puff and stir until smooth, then keep adding cornstarch 1 tablespoon at a time and knead on the cornstarch-dusted wax paper until the mixture pulls away and feels thick enough to handle.

How can we adapt this activity for younger children or older kids?

For toddlers and preschoolers, have an adult do the microwave heating and stirring and pre-measure the 1 cup of mini marshmallows and cornstarch while the child helps with cooling, kneading, and stretching under supervision, and for older kids let them measure, microwave with adult oversight, knead until stretchy, and handle putting the slime into the airtight container themselves.

How can we personalize or enhance our edible slime after making it?

Stir a drop of food-safe gel coloring or a pinch of cocoa powder or vanilla extract into the warm marshmallow goo before adding all the cornstarch, knead in edible glitter or sprinkles once cooled, then store your creation in the airtight container and share a photo on DIY.org.