Valentines goop or oobleck! Red hots are a fun Valentine’s Day treat, but they were a little too hot for us! Instead, we turned them into Valentine’s goop for a bit of science and sensory play. Goop, or oobleck as it is often referred to, is super quick and easy to make and is a fun science lesson for kids. We gave it a holiday theme with Red Hots! Holiday-themed science activities are our favorite ways to play!

Red Hots Valentines Goop or Oobleck for Science

Valentines Goop Science Activity Valentines oobleck science sensory play

Quick and easy red hots Valentines Goop science sensory play is a real hit! This stuff is so easy to make with only 2 ingredients needed for the basic recipe!


You will want to raid your kitchen cupboards for this one! Making Valentines goop is as simple as grabbing to household staples, water and cornstarch and mixing them up! However, it’s the ratio of water to cornstarch that is so important to this oobleck recipe.

What Is Valentines Goop or Oobleck?

It is usually a mixture of cornstarch and water. Roughly a 2:1 ratio but you can tinker with the ratio to find the desired consistency that still maintains the properties of goop and oobleck. What’s the science behind it?

Well, it’s solid. No, wait it’s a liquid! Wait again, it’s both! Very fascinating to be exact. Pick up solid chunks,  pack it into a ball and watch it ooze into a liquid. This is called a non-Newtonian liquid, a substance that acts like both a liquid and a solid.

Also see our candy hearts oobleck, click here.

Goop or Oobleck Supplies

Open the cupboards and get set for a little kitchen science…

—>See them all here: Best Valentine’s Day Science for Kids

  • cornstarch
  • water
  • Red Hots candies (or try candy hearts as shown above)
  • food coloring
  • cookie sheet
  • bowl and spoon

How To Make Oobleck or Goop

Simply mix up about a cup of cornstarch and 1/2 cup of water! You can adjust the ratios as needed, but this recipe is a general guideline! Pour and spoon onto a cookie sheet or pie plate and set out bowls of goodies (really anything can be used for sticking into the oobleck!), add a pair of tweezers and play!

Valentines Goop Valentines Oobleck science activity sensory play set up

Valentines Goop Science for Sensory Play

This Valentines Goop is one of our 12 favorite sensory play recipes from kitchen cabinet ingredients. Make sure to check them all out for unique play anytime! It’s a bit messy and I always provide my son with some sort of spoon or tool to ease his transition into using his fingers!

Plus the red hot cinnamon candies gave off a delightful scent. Of course, we tried a few but a bit spicy.

—->Also check out: Valentine’s Day Slime Recipes

valentines goop science activity sensory play

This time we added a new scientific experiment to our Valentines goop. I challenged him to explore what happens when you add more water. Then I challenged him to find out what happens when you add more cornstarch.

He took the Valentines goop all the way to a liquid and then all the way to a thick almost solid and then back to regular Valentines goop again. This was such an easy way to have him make predictions, test his ideas, and explore change!

Valentines Goop Science Activity exploring change


Oobleck is a fun substance made from a mixture of cornstarch and water. It’s a bit messy too!

A mixture is a material made up of two or more substances to form a new material which is our oobleck! Kids can also explore liquids and solids which are states of matter. Here we are combining a liquid and a solid, but the mixture doesn’t become one or the other.

A solid has its own shape whereas a liquid will take the shape of the container it is put into. Oobleck is a bit of both!

That’s why oobleck is called a non-Newtonian fluid. This means it is neither a liquid nor a solid but a bit of both! You can pick up a clump of the substance like a solid and then watch it ooze back into the bowl like a liquid.

Touch the surface lightly and it will feel firm and solid. If you apply more pressure,  your fingers will sink into it like a liquid.


Want to experiment with viscosity? Change the ratios of water to cornstarch! Viscosity is the physical property of fluids and how thick or thin they are including how they flow. You could even try to make oobleck with flour, powder, or baking soda and compare the similarities and differences.

We have also made this cornstarch slime with just glue and cornstarch.

Although Valentines goop is a cool science activity, it’s also great sensory play too. We have done a few goops or ooblecks,  and he is starting to understand the science behind it a bit more each time. I highly recommend finding fun ways to repeat science experiments to increase understanding! We are always finding new ways to try out similar experiments!

 Valentines Goop for quick science play!

Make sure to check out all of our Valentine’s Day  Science too!


  1. I was wondering if you could start including a link on your posts for a PDF that we could print and use to help organize our fun? That way we could have a picture, list of items, and directions on hand.
    I LOVE your site and can’t wait to get started!!!

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