How to Make Goop With Cornstarch

Goop, also known as oobleck or slime, is a popular DIY project loved by both kids and adults alike. It’s a non-Newtonian fluid that behaves like a liquid when poured but will turn solid when pressure is applied. Making goop with cornstarch is not only fun and easy, but it’s also a great way to introduce scientific concepts to children.

How to Make Goop With Cornstarch

In this guide, we will show you how to make goop with cornstarch using just a few simple ingredients and provide some tips for creating different variations. If you’re ready to get your hands dirty, let’s dive in!

Understanding the Science Behind Goop

Before we dive into the recipe, it’s important to understand the science behind goop. Goop is made from a mixture of cornstarch and water, which creates a suspension that can behave like both a solid and a liquid. When pressure is applied to the goop, such as squeezing or stirring it, the cornstarch particles are forced together to create a solid-like structure. Once the pressure is released, the cornstarch particles move apart and allow the goop to flow like a liquid again.

This phenomenon is known as shear thickening, and it occurs because of the nature of cornstarch particles. Cornstarch consists of long chains of sugar molecules called amylose and amylopectin. When mixed with water, these chains can tangle and form a thick, stretchy gel. When force is applied, the chains become aligned and intertwined, creating a solid-like structure.

Supplies You Will Need to Make Goop With Cornstarch

1. 1 cup of cornstarch

2. 1/2 cup of water

3. Food coloring (optional)

4. Mixing bowl

5. Spoon or whisk

6. Measuring cups

7. A flat surface or tray for playing with the goop (optional)

Step-by-step Guidelines on How to Make Goop With Cornstarch

Step 1: Prepare Your Workspace

Before you start making goop, it’s important to prepare your workspace. Lay down some old newspapers or a plastic tablecloth to protect your surface from any spills or stains. Preparing your workspace will also make cleaning up much easier.

Prepare Your Workspace

This is a great opportunity to involve your kids in the process and teach them about cleanliness and organization. If you’re making goop with younger children, make sure to supervise them at all times.

Step 2: Mix Cornstarch and Water

In a mixing bowl, combine 1 cup of cornstarch and 1/2 cup of water. You can adjust the ratio if you want a thicker or thinner consistency. If you want to add color to your goop, you can mix in a few drops of food coloring at this stage.

The goop will turn out white if you don’t add any color. Make sure to mix the ingredients thoroughly until there are no clumps of cornstarch left. If your goop is too thick, you can add a little bit more water, and if it’s too runny, you can add more cornstarch.

Step 3: Experiment with Different Textures and Consistencies

Once you have successfully made your goop, it’s time to get creative! You can experiment with different textures and consistencies by adding more water or cornstarch to your mixture. Try making a batch of goop that is thicker than the original recipe and see how it behaves differently. You can also try mixing in glitter, beads, or other small objects to add a sensory element to your goop.

Step 4: Play and Have Fun!

Now that you have made your goop, it’s time to play with it! Pour the goop onto a flat surface or tray and start exploring its properties. You can poke it, squeeze it, roll it, or even try to make shapes with it. You will notice that the goop behaves differently depending on how you interact with it. Encourage your kids to experiment and come up with their ways of playing with the goop. Make sure to have towels and wet wipes nearby for easier clean-up.

Following these simple steps, you can make goop with cornstarch in just a few minutes. Remember to have fun and be creative with your goop. You can also try making different variations by adding scents, textures, or colors. Goop is an excellent activity for kids to learn about science and sensory play while having loads of fun.

Time to Play With It

So next time you’re looking for a fun and educational activity, give Goop with cornstarch a try!  So why wait? Gather your supplies and get ready to make some mesmerizing goop! Share your creations with us in the comments below. Happy experimenting!

Additional Tips and Tricks to Make Goop With Cornstarch

1. If you want a more colorful goop, add a few drops of food coloring to the mixture before adding water. This will create a fun and vibrant goop that kids will love playing with.

2. If your goop becomes too sticky, simply add a small amount of cornstarch and continue mixing until it reaches the desired consistency.

3. To make your goop smell great, try adding a few drops of essential oils to the mixture before adding water. Lavender and peppermint are great options for a calming or energizing goop experience.

4. For added texture and sensory stimulation, mix small objects like beads, glitter, or even dried flowers into your goop.

5. Cornstarch goop can be used as a fun and educational tool for young children to learn about non-Newtonian fluids. Encourage them to experiment and explore the properties of this unique substance.

6. To clean up any goop spills, simply wipe with a damp cloth or paper towel. Avoid using hot water as it can cause the goop to harden and become more difficult to remove.

7. Consider adding a little bit of dish soap to your goop mixture for a stretchier and more slippery texture. This is especially fun when playing with Goop on a plastic sheet or in a large container.

8. To make your goop last longer, store it in an airtight container or ziplock bag after playtime. This will prevent it from drying out and allow you to use it again and again.

Store It in an Airtight Container

9. If your goop starts to dry out, simply knead in a small amount of water until it reaches the desired consistency. Be careful not to add too much water as it can make the goop too runny.

10. Most importantly, have fun and let your creativity run wild when making and playing with cornstarch goop! There are endless possibilities and variations to explore with this simple but fascinating substance.

So go ahead and experiment, and don’t be afraid to get a little messy!

Following these tips and tricks will ensure that you have a fun and successful experience making goop with cornstarch. Whether it’s for educational purposes or just pure entertainment, cornstarch goop is a fantastic sensory activity for children of all ages.

So gather your materials and get ready to create some slimy, gooey, and fascinating goop!  Remember to always supervise children when playing with Goop and make sure to clean up any spills or messes afterward. Have fun and enjoy the wonderful world of cornstarch goop!  Happy creating! 

Things You Should Consider to Make Goop With Cornstarch

1. The first thing you need to consider when making goop with cornstarch is the consistency. Cornstarch goop is meant to be a non-Newtonian fluid, which means its viscosity changes depending on the force applied to it. This unique property allows for fun and interesting experiments, but it also means that you need to get the right consistency for it to work properly.

2. The ratio of cornstarch to water is key in achieving the perfect consistency for your goop. Too much cornstarch and it will be too thick, making it difficult to mix and play with. Too much water and it will be too runny, losing its non-Newtonian properties. A good rule of thumb is to use a 1:1 ratio, but you may need to adjust it slightly depending on the brand of cornstarch and the humidity in your environment.

The Ratio of Cornstarch to Water

3. Another factor to consider is the temperature of the water when mixing with cornstarch. Cold water will make for a thicker goop while warm water will make it thinner. Experiment with different temperatures to find what works best for you and your desired consistency.

4. Adding food coloring or glitter can add a fun and colorful element to your goop, but be careful not to overdo it. Too much coloring can affect the consistency of your goop and too much glitter can make it difficult to clean up afterwards.

5. For the cornstarch and water to fully combine and create non-Newtonian properties, it is important to mix them slowly. Gradually add the water to the cornstarch and mix continuously until fully incorporated. You may need to use your hands to get a smooth and consistent mixture.

6. As with any messy activity, be sure to protect your work surface by using a plastic tablecloth or old newspapers. This will make for an easier clean-up afterward.

7. Have fun with your goop! Experiment with different textures by adding more or less cornstarch or water. You can also add other materials such as sand, rice, or small toys to create a sensory experience. Just be sure to use caution and supervise young children when playing with these additional elements.

8. When you are finished playing with your goop, store it in an airtight container or ziplock bag to prevent it from drying out. If it does dry out, simply add a little bit of water and mix until you reach the desired consistency again.

Following these considerations will ensure that you have a successful and enjoyable experience making goop with cornstarch. Get creative and have fun exploring the unique properties of this simple but fascinating substance!  Some additional ideas for experiments could include testing the effects of different liquids, such as oil or vinegar, on the goop’s consistency or seeing how long it takes for the goop to return to its solid state after being disturbed.

The possibilities are endless, so let your imagination run wild! Just be sure to always clean up afterward and dispose of the goop properly when you are finished playing with it. Happy goop-making! 

Troubleshooting Common Issues of Making Goop With Cornstarch

1. Too Runny or Too Thick:

Goop is Too Runny

One of the most common issues when making goop with cornstarch is getting the consistency just right. If your goop is too runny, it means you added too much water or not enough cornstarch. On the other hand, if your goop is too thick, it means you added too much cornstarch or not enough water.

To fix a runny goop, simply add small amounts of cornstarch at a time until you reach the desired consistency. If your goop is too thick, slowly pour in more water while continuously mixing until it becomes smoother and less stiff.

2. Not Holding Shape:

Another issue that may arise when making goop with cornstarch is that it does not hold its shape. This could be due to not using enough cornstarch or not mixing it well enough. Make sure you are following the recipe and adding the correct amount of cornstarch.

To fix this issue, simply add more cornstarch and mix until it reaches the desired consistency. You can also try kneading the goop with your hands to help distribute the ingredients more evenly.

3. Turning Black:

If your goop starts to turn black, it means that the cornstarch has started to break down and is no longer usable. This could be due to exposing the goop to heat for too long or using old cornstarch. Make sure you are using fresh ingredients and not leaving the goop in direct sunlight for extended periods.

To prevent this issue, store your goop in an airtight container and keep it away from heat sources. If the goop does turn black, unfortunately, there is no way to fix it and you will need to make a new batch.

4. Not Stretchy:

Have a Stretchy Consistency

Some people prefer their goop to have a stretchy consistency, similar to slime. If your goop is not stretchy enough, it could be due to not using enough water or adding too much cornstarch.

To fix this issue, try adding more water and continuously mixing until you reach the desired consistency. You can also add a small amount of glue or liquid laundry detergent to help make the goop more elastic.

5. Not Smooth:

If your goop has a gritty or lumpy texture, it could be due to not mixing the ingredients well enough or using old cornstarch. Make sure you mix the ingredients thoroughly and check the expiration date on your cornstarch.

To fix this issue, try kneading the goop with your hands until it becomes smoother. You can also strain the goop through a sieve to remove any lumps. If the issue persists, it may be time to use fresh ingredients.

Following these troubleshooting tips should help you create the perfect goop every time. Remember to always double-check your measurements and ingredients, and have fun experimenting with different colors and textures! Happy goop-making! 

Precautions Need to Be Followed for Making Goop With Cornstarch

1. First and foremost, it is important to wash your hands thoroughly before handling any ingredients. This will help prevent any bacteria or germs from being introduced into the mixture.

2. Always use a clean container and utensils when making goop. Any dirt or debris can affect the texture and consistency of the final product.

3. Make sure all ingredients are fresh and have not expired. This includes the cornstarch, water, and any additional ingredients like food coloring or glitter.

4. When adding different colors to your goop, be sure to use food-safe dyes or natural alternatives. Avoid using non-edible materials that could potentially harm children if ingested.

5. Keep a close eye on children while they are playing with goop. While it is non-toxic, it should not be ingested and could cause choking if a large amount is consumed.

6. Clean up any spills or messes promptly to prevent the goop from drying and becoming difficult to clean.

7. Store homemade goop in an airtight container when not in use. This will help prevent it from drying out and extend its shelf life.

8. If the goop starts to smell or change color, discard it and make a fresh batch. This could be a sign of bacterial growth and is not safe for play.

Discard It and Make a Fresh Batch

Following these precautions will ensure a safe and enjoyable experience when making goop with cornstarch. It is always important to prioritize safety when working with any ingredients, especially when children are involved. Have fun and get creative with different colors and textures, but remember to be cautious and responsible throughout the entire process. Happy goop-making!


With the above outline, you can easily learn how to make goop with cornstarch and water. It is a simple, fun, and inexpensive activity that can keep children entertained for hours. Not only does it provide sensory play but it also introduces scientific concepts such as non-Newtonian fluids.

You can also experiment with different ratios of cornstarch and water to create different consistencies. You can add food coloring or glitter for added visual appeal. Additionally, you can try adding other ingredients such as dish soap or flour to see how it affects the texture and properties of the goop. Happy experimenting!

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Loren Jones

Hi, my name is Loren. I live with my husband and 4 lovely kiddos in the Eastern part of San-fransisco. I have a smart beautiful,curious 6 year old daughter, a handsome 11-year-old son, an intelligent and tech geek 15 years old son and a creative, artistic 12-year-old stepson. With each of my kids being five years apart, I feel that I’m now continually phasing in and out of each stage of parenting! I’ve learned a lot about the way children learn and behave, especially in a school setting with regards to curriculum. I enjoy sharing that insight through my writing and hope that it can help others.

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