Fun, hands-on science made from just cornstarch and water! Oobleck is a non-Newtonian fluid, meaning it acts like a solid when you squeeze it but flows like a liquid when you let go.
Below are teacher-tested recipes, including a large batch for a class of 30, individual cup servings, and several fun variations.
🧼 Cleanup Tips (Important for Teachers!)
Wipe hands with dry paper towelsbefore rinsing with water.
Throw Oobleck in the trash, not the sink.
Warm water loosens dried Oobleck on tables.
Keep a small broom/dustpan handy for dried bits.
🧪Oobleck Recipe for a Class of 30
This recipe makes enough for every student to have roughly ½ cup of Oobleck.
Ingredients
10 cups cornstarch
6 cups water
Green food coloring (or any color)
Extra cornstarch for thickening
Instructions
Pour 6 cups of water into a large tub or bowl.
Add food coloring until the water reaches your desired color.
Slowly add 10 cups of cornstarch, stirring with your hands.
Adjust:
Too runny → add more cornstarch
Too thick → add small splashes of water
Scoop portions into paper cups for each student.
Teacher Tip: Low-Mess Version
Put ⅓ cup cornstarch into each student’s cup before class. During the activity, walk around with colored water and pour 3–4 tablespoons into each cup. Students mix their own Oobleck: way less mess, same fun.
🔽 Scaled-Down Oobleck Recipes
These use the standard 2:1 cornstarch-to-water ratio.
Small Group (6–8 kids)
3 cups cornstarch
1½ cups water
Pair or Center (2–3 kids)
1 cup cornstarch
½ cup water
Single Student Cup
⅓ cup cornstarch
3–4 tbsp colored water
🌈 Fun Oobleck Variations
Perfect for themes, sensory bins, or science extensions.
⭐ Classic Oobleck
The standard recipe — no extras needed. 2 parts cornstarch + 1 part water
🌈 Colorful Oobleck
Mix food coloring or liquid watercolor into the water before adding cornstarch.
Great for: Holidays, School colors, Rainbow centers
✨ Glitter / Sparkle Oobleck
Add 1 tablespoon fine glitter per batch.
Tip: Use biodegradable glitter for younger children.
Note: Do not pour glitter mixtures down the drain.
🧁 Edible / Taste-Safe Oobleck
Safe for toddlers and sensory play. This version is completely non-toxic.
Ingredients: Cornstarch + Water + Kool-Aid powder, food coloring, or vanilla extract
❄️ Frozen Oobleck
Fun for Arctic or winter themes.
Fill muffin cups with prepared Oobleck.
Freeze overnight.
Children explore the changing texture as it thaws.
🌌 Galaxy Oobleck
Mix black or deep purple watercolors + silver glitter.
Optional: star confetti (remove after play).
🟣 Color-Changing Oobleck (Thermochromic)
Add a pinch of thermochromic pigment that changes color with temperature.
Great for older students or STEM centers.
