Easy Cornflour Slime Recipe: Fun DIY For Kids!

Sep 7, 2025 by Lucia Rojas 47 views

Hey guys! Ever wanted to dive into a super fun and squishy activity that’s both easy to make and totally mesmerizing? Well, you’re in the right place! We’re going to explore the magical world of cornflour slime, also known as Oobleck. This isn't your typical slime; it's a non-Newtonian fluid, which means it acts like a solid when you apply pressure and a liquid when you don't. Cool, right? Making cornflour slime is an awesome science experiment and a super entertaining sensory activity all rolled into one. Plus, it’s incredibly simple, requiring just a few ingredients you probably already have in your kitchen. So, grab your mixing bowls and let's get started on this gooey adventure!

What is Cornflour Slime (Oobleck)?

Before we dive into the recipe, let's chat a bit about what makes cornflour slime, or Oobleck, so special. The term "Oobleck" comes from the Dr. Seuss book "Bartholomew and the Oobleck," where a gooey green substance falls from the sky and causes all sorts of chaos. Our version, however, is much more manageable and a lot less messy (if you’re careful, haha!). Scientifically speaking, Oobleck is a non-Newtonian fluid. This fancy term means that its viscosity (or thickness) changes depending on the stress applied to it. When you stir it slowly or let it sit, it flows like a liquid. But when you squeeze it, punch it, or apply quick pressure, it turns solid! This unique behavior makes playing with cornflour slime a truly fascinating experience. It’s like magic in your hands, and it’s a fantastic way to introduce kids (and adults!) to basic scientific principles in a fun and engaging way. Think about it – you can pick up a handful of this goo, roll it into a ball, and it stays solid. But as soon as you stop applying pressure, it melts back into a liquid right before your eyes. This is all thanks to the way the cornstarch particles interact with water. When pressure is applied, the particles come together and create a temporary solid structure. When the pressure is released, the water lubricates the particles, allowing them to slide past each other and return to a liquid state. Understanding this simple science makes the whole activity even more rewarding. You’re not just making slime; you’re creating a mini science lesson right in your kitchen! So, get ready to impress your friends and family with your newfound Oobleck expertise. Now, let's get to the fun part – making the slime!

Ingredients You'll Need

Alright, let’s gather our supplies! One of the best things about cornflour slime is that you only need a couple of basic ingredients. This makes it a super accessible activity for any day, whether you’re planning ahead or just looking for a spontaneous project. Here’s what you’ll need:

Cornflour (Cornstarch): This is the star of the show! You’ll need about 1 box (16 ounces or 450 grams) of cornflour. Make sure you’re using cornflour and not another type of flour, as the unique properties of cornflour are what give Oobleck its amazing texture. Cornstarch is the key ingredient that allows the mixture to act as a non-Newtonian fluid, solidifying under pressure and liquefying when at rest. The fine particles of cornstarch suspended in water create this fascinating effect. Trust me, without the cornstarch, you’ll just end up with a watery mess!
Water: Plain old tap water works perfectly. You’ll need about 1 cup, but it’s best to add it gradually to get the right consistency. The ratio of cornflour to water is crucial for achieving that perfect Oobleck texture. Too much water, and it will be too runny; not enough, and it will be too dry and crumbly. The water acts as the medium in which the cornstarch particles can move and interact. When you apply pressure, the water is forced out from between the particles, causing them to pack together and solidify. When the pressure is released, the water flows back in, and the mixture returns to its liquid state. It’s all about balance, guys!
Optional: Food Coloring: If you want to add a pop of color to your cornflour slime, food coloring is the way to go! Liquid food coloring works best, but gel food coloring can also be used (just make sure to mix it well). This is where you can really get creative and personalize your slime. You can choose vibrant colors like blue, green, or pink, or even mix colors to create your own unique shades. Imagine a swirling galaxy of colors right in your hands! Adding food coloring doesn’t affect the science behind the Oobleck, but it definitely boosts the fun factor. It’s also a great way to tie the slime into a specific theme, like spooky black slime for Halloween or festive red and green for Christmas. So, don’t be afraid to experiment and let your imagination run wild!

And that’s it! Just three simple ingredients (or two, if you skip the food coloring) are all you need to create this amazing substance. Now that we’ve got our supplies ready, let’s move on to the step-by-step instructions for making your very own batch of cornflour slime.

Step-by-Step Instructions

Okay, guys, now for the fun part – actually making the cornflour slime! Don't worry, this is super easy and takes just a few minutes. Follow these simple steps, and you'll have your own batch of Oobleck in no time. Let’s get started:

Combine Cornflour and Water: Grab a large mixing bowl – you'll want plenty of space to play around with the slime later. Pour the entire box of cornflour (about 16 ounces or 450 grams) into the bowl. This is your base, the foundation of your Oobleck masterpiece. Now, slowly add the water, about ¼ cup at a time. The key here is to add the water gradually. You don’t want to dump it all in at once, or you might end up with a consistency that’s too watery or too thick right off the bat. As you add the water, start mixing with your hands or a spoon. At first, it will feel like you’re just making a paste, but trust the process! The magic is about to happen. Keep mixing until the cornflour starts to combine with the water, forming a thick, white mixture. The consistency will be a bit lumpy at this stage, but that’s perfectly normal. Just keep adding water little by little and stirring until you reach the desired texture.
Mix Until the Right Consistency: This is where things get a little tricky, but don’t worry, you’ll get the hang of it! The goal is to achieve a consistency where the mixture feels solid when you apply pressure but turns liquid when you let it sit. It’s a bit like a magic trick in your hands! Keep adding water a tablespoon at a time and mixing until you reach this unique texture. You'll know you're getting there when you can punch the surface of the mixture and it feels solid, but if you slowly dip your fingers in, they'll sink right through. If you accidentally add too much water and the mixture becomes too runny, don’t panic! Just add a little more cornflour to balance it out. Similarly, if it’s too thick, add a bit more water. This process might take a little trial and error, but that’s part of the fun! Think of it as a science experiment, and you’re the lead scientist. The perfect Oobleck consistency is a fascinating balance of solid and liquid, and you’ll know it when you feel it. The mixture should be thick enough to pick up and roll into a ball, but it should also ooze and flow like a liquid when you stop applying pressure. Once you’ve nailed the consistency, you’re ready to move on to the next step.
Add Food Coloring (Optional): If you’re going for a colorful slime, now’s the time to add your food coloring. A few drops go a long way, so start with a small amount and add more until you achieve your desired shade. Liquid food coloring works best, as it mixes into the slime more easily. Gel food coloring can also be used, but you might need to mix it a bit more thoroughly to avoid streaks. Adding the food coloring is a fun way to personalize your Oobleck and make it even more visually appealing. You can choose a single color for a classic look, or get creative and swirl in multiple colors for a mesmerizing effect. Imagine a vibrant rainbow of slime in your hands! To add the food coloring, simply drop a few drops into the mixture and start mixing with your hands or a spoon. The color will gradually spread throughout the slime, transforming it into a vibrant, eye-catching substance. If you’re using multiple colors, try adding them one at a time and gently swirling them together for a marbled effect. This can create some truly stunning patterns in your Oobleck. Just remember, food coloring can sometimes stain, so it’s a good idea to protect your work surface and wear old clothes or an apron. Once the color is mixed in, your cornflour slime is ready to play with! So, go ahead and dive in – it’s time to experience the amazing properties of Oobleck firsthand.

And there you have it! You’ve successfully made your own batch of cornflour slime. Wasn't that easy? Now, let’s talk about how to play with this amazing creation and make the most of its unique properties.

How to Play with Cornflour Slime

Alright, guys, you've made your cornflour slime, and now it's time for the real fun to begin! Playing with Oobleck is an experience unlike any other. Its unique properties make it endlessly fascinating and a great way to explore the science of non-Newtonian fluids firsthand. Here are some awesome ways to play with your cornflour slime and really get the most out of it:

Punch It: Seriously, go ahead and punch it! One of the coolest things about Oobleck is how it turns solid when you apply pressure. Try giving the surface a quick, firm punch. You'll feel it resist like a solid, but if you leave your hand there, it will slowly sink in as the slime turns back into a liquid. This is a fantastic demonstration of Oobleck's non-Newtonian behavior. The rapid force of your punch causes the cornstarch particles to pack together tightly, creating a temporary solid structure. It’s like a liquid that suddenly becomes a solid under your touch! This never gets old, trust me. You can even challenge your friends to a punching contest – who can make the biggest dent in the Oobleck without it splashing? Just make sure you’re playing in a safe area, as things can get a little messy (but that’s part of the fun, right?).
Roll it into a Ball: Pick up a handful of the slime and start rolling it between your palms. The pressure you apply will cause the Oobleck to solidify, allowing you to form it into a ball. Keep rolling it quickly, and you'll have a solid sphere in your hands. But here's the magic: as soon as you stop applying pressure, the ball will start to melt and drip back into a liquid! This is a classic Oobleck trick that’s sure to impress anyone who sees it. The constant pressure keeps the cornstarch particles tightly packed, maintaining the solid shape. But as soon as the pressure is released, the particles can move freely again, and the water lubricates them, causing the slime to flow. It’s a perfect example of how Oobleck behaves differently under different conditions. Try making several small balls and juggling them – it’s a fun challenge that requires some speed and coordination. Or, you can roll a large ball and watch it slowly flatten out into a puddle of goo. The possibilities are endless!
Run Across It: Okay, this one might require a bit more Oobleck and a large container, but it's totally worth it if you can pull it off! If you have enough cornflour slime, you can actually run across the surface without sinking. The trick is to move quickly and apply constant pressure. If you stop moving, you’ll start to sink into the liquid. This is a spectacular demonstration of the solid-like properties of Oobleck under pressure. When you run across it, the force of your feet compacts the cornstarch particles, creating a temporary solid surface. But if you stand still, the particles have time to move apart, and you’ll sink right in. This experiment is often done with a large pool of Oobleck, and it’s a huge hit at science museums and events. While it might not be practical to set up a giant Oobleck pool in your living room (unless you’re feeling super adventurous!), you can still get a sense of the effect by trying to quickly push your hand across the surface of a smaller container of slime. You’ll feel the resistance and the temporary solidity.
Slowly Sink Your Fingers In: On the flip side, try slowly dipping your fingers into the slime. Instead of feeling resistance, your fingers will sink right in as the Oobleck behaves like a liquid. This contrast is part of what makes playing with cornflour slime so fascinating. It's a sensory experience that engages your sense of touch in a unique way. The slow, gentle motion allows the cornstarch particles to move out of the way, and the water acts as a lubricant, allowing your fingers to slip through the mixture. This is the opposite of the punching effect, where rapid pressure causes the particles to pack together. The slow sinking sensation is almost meditative, and it’s a great way to relax and explore the liquid side of Oobleck. You can even try wiggling your fingers around in the slime to feel the unique texture and the way it flows around your hand.
Use Cookie Cutters and Molds: Add another layer of fun by using cookie cutters, molds, and other toys to play with your Oobleck. Press a cookie cutter into the slime, and it will hold its shape like a solid. Then, watch as the shape slowly melts and the slime flows out. This is a great way to experiment with Oobleck’s dual nature and create interesting patterns and designs. You can use star-shaped cookie cutters, animal molds, or even just simple cups and containers. The possibilities are endless! Pouring the Oobleck into molds and letting it set for a few seconds before turning it out can create some really cool temporary sculptures. The way the slime holds its shape for a moment before melting back into a liquid is mesmerizing. This activity is also a great way to introduce kids to concepts like shape, volume, and texture. They can experiment with different molds and see how the Oobleck behaves in each one.

Playing with cornflour slime is all about experimentation and discovery. There are no rules, so feel free to get creative and try new things! The more you play, the more you’ll appreciate the amazing properties of this fascinating substance. So, go ahead, dive in, and have some fun!

Tips for Success

Making cornflour slime is pretty straightforward, but a few tips can help ensure your Oobleck adventure goes smoothly. Here are some pointers to keep in mind for a successful slime-making experience:

Add Water Gradually: This is the golden rule of Oobleck! As we discussed earlier, the key to the perfect consistency is adding the water slowly, a little bit at a time. If you dump all the water in at once, you’re much more likely to end up with a mixture that’s either too runny or too thick. Adding the water gradually allows the cornstarch particles to properly hydrate and interact with the water, creating the unique non-Newtonian fluid properties. Start with about ¼ cup of water for a 16-ounce box of cornflour, and then add more a tablespoon at a time, mixing thoroughly after each addition. This gives you more control over the consistency and allows you to adjust as needed. It’s much easier to add more water than it is to take it away, so patience is key! Mixing the water in slowly also helps to prevent clumps from forming, ensuring a smoother and more consistent slime. So, remember, slow and steady wins the Oobleck race!
Don't Be Afraid to Adjust: Every batch of cornflour slime is a little different, and that’s perfectly okay! The exact amount of water you need might vary slightly depending on factors like humidity and the specific brand of cornflour you’re using. So, don’t be afraid to adjust the recipe as you go. If your slime is too thick and difficult to mix, add a little more water, a tablespoon at a time, until you reach the desired consistency. On the other hand, if your slime is too runny, add a bit more cornflour to thicken it up. It’s all about finding the right balance. The perfect Oobleck should feel solid when you apply pressure, but it should also flow like a liquid when you let it sit. Think of it as a science experiment, and you’re the lead investigator! Experimenting with the proportions is part of the fun, and it’s a great way to learn about the properties of non-Newtonian fluids. So, don’t worry if your first batch isn’t perfect – just keep adjusting until you get it right. With a little practice, you’ll become an Oobleck master in no time!
Use a Large Bowl: Trust me on this one – you’ll want plenty of space to play! Cornflour slime can be surprisingly messy, and using a large bowl helps to contain the goo and prevent it from spilling over the sides. A large bowl also gives you more room to mix the ingredients and explore the slime’s unique properties. You can really get your hands in there and play around without worrying about making a huge mess. If you’re planning on doing some of the more adventurous Oobleck activities, like running your fingers across the surface or using cookie cutters, a large bowl is essential. You might even consider using a plastic tub or a shallow bin if you want to make a really big batch of slime. The bigger the container, the more room you have to experiment and have fun. So, before you start mixing, make sure you’ve got a spacious workspace ready to go. Your future self (and your kitchen counter) will thank you!

Storage and Cleanup

Okay, guys, we’ve had a blast making and playing with our cornflour slime, but now it’s time to talk about storage and cleanup. While Oobleck is super fun, it can be a bit messy, so knowing how to handle it properly is key. Here’s the lowdown:

Storage: When you’re done playing, the best way to store your cornflour slime is in an airtight container. This will prevent it from drying out and becoming hard. A plastic container with a lid or a resealable bag works perfectly. Make sure to squeeze out any excess air before sealing the container. You can store Oobleck at room temperature, and it should last for several days, or even weeks, if stored properly. However, keep in mind that the slime may start to develop a slightly sour smell after a while, which is a sign that it’s time to make a fresh batch. If the slime does dry out, you can try adding a little bit of water and mixing it to rehydrate it. But if it’s too far gone, it’s best to just start fresh. Making a new batch of Oobleck is so quick and easy that it’s not really a big deal if you have to toss the old one. Proper storage will help you get the most out of your slime and ensure that it’s ready for playtime whenever you are.
Cleanup: Cleanup is surprisingly easy! Since cornflour slime is made with just cornflour and water, it’s non-toxic and washes away easily with water. If you spill any Oobleck, simply wipe it up with a damp cloth or sponge. Avoid pouring large amounts of Oobleck down the drain, as it can potentially clog your pipes. Instead, dispose of the used slime in the trash. If you’ve got Oobleck stuck on your hands or clothes, just rinse it off with water. It might take a little bit of scrubbing, but it should come off without too much effort. If you’ve added food coloring to your slime, be aware that it might stain certain surfaces or fabrics. To prevent stains, it’s a good idea to protect your work area with a tablecloth or plastic covering. Wearing old clothes or an apron while playing with Oobleck is also a smart move. Overall, cleanup is a breeze compared to some other slime recipes that involve glue and other sticky ingredients. So, don’t let the potential for mess deter you from enjoying this amazing substance. With a few simple precautions, you can keep your Oobleck playtime fun and stress-free.

Get Ready to Have Some Gooey Fun!

So there you have it, guys! Making cornflour slime is a fantastic activity that’s both educational and incredibly fun. Whether you’re looking for a science experiment to do with your kids, a sensory activity to engage their senses, or just a cool way to spend an afternoon, Oobleck is the perfect choice. It’s easy to make, requires just a few simple ingredients, and provides hours of entertainment. The unique properties of this non-Newtonian fluid are truly fascinating, and playing with it is a great way to learn about science in a hands-on way. From punching it to rolling it into a ball to sinking your fingers in, there are so many ways to explore the magic of Oobleck. Plus, cleanup is a breeze, so you don’t have to worry about making a huge mess. So, what are you waiting for? Grab some cornflour, water, and maybe a little food coloring, and get ready to dive into the wonderful world of cornflour slime! You’re guaranteed to have a gooey good time!