Create a walking rainbow by filling jars with colored water. 

Science Fair Projects for ​Grades K-2

1. Walking Rainbow
Demonstrate your knowledge of capillary action and color mixing by creating a walking rainbow using paper towels and food dye.

2. Coffee Filter Chromatography
Be a color detective with this hands-on activity that explains how colors are created by mixing various color molecules and solutions.

3. Lemon Science
This simple experiment covers all your science fair bases by creating a colorful fizzy reaction right in a lemon. Lemon Science is a great way to test what happens when you mix an acid and a base together.

4. Solar S’More Oven
Save those pizza boxes to help kids turn them into a Solar S’More Oven. Kids can hypothesize if a cloudy day will affect their delicious results.

5. Apple Science
How do I keep my apple slices from turning brown? This engaging apple experiment will illustrate the concept of oxidation over a short period of time as well as allow your child to draw conclusions about what substance will prevent the apples from turning brown.

6. Grow Food from Garbage
Before you toss those celery scraps, regrow them into new plants! There are a handful of vegetables that can be regrown and allow children to exhibit plants' need to thrive.

7. Turn a Penny Green
Learn about oxidation, chemical reactions, and the principles of corrosion all with a penny. This popular Penny Experiment empowers kids to hypothesize and draw their own conclusions about why some pennies turn green over time.

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Who knew blood could be so delicious? Make a 'blood model' out of candy.

Easy Science Fair Options for Grades 3-5

8. Stir Together a Blood Model
Marshmallows, corn syrup, and red sprinkles are a delicious way to talk about blood components at the science fair. Create this hands-on, kid-friendly model with some yummy ingredients.

9. Volcano
Science Fair Volcanoes combine elements of earth science, chemistry, geology, and pure fun. There are a lot of engaging ways to create this science fair classic.

10. Elephant Toothpaste
Grab your safety goggle and a plastic water bottle, it’s time to make elephant toothpaste! Learn about catalysts and solutions while concocting this larger-than-life experiment.

11. Potato Battery
Harness the power of electricity in a potato! OK, so potatoes aren’t electric, but kids can use one to conduct an electrochemical reaction for this chemistry science fair project.

12. Science of Slime
Sure, slime is fun! But, it’s also a great way to play with non-Newtonian liquids, states of matter, and create a polymer. Get our favorite slime recipes.

13. Borax Crystals
You can grow crystals at home with water, borax, pipe cleaners, and thread.

14. Science of Condensation: How to Make Frost
No matter what the weather may be outside, can create frost in any classroom or all-purpose room. Combine salt, crushed ice, and a tin can and watch frost grow right before your eyes.

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Get out the lab coats to extract DNA from a strawberry.

Science Fair Projects for Middle School 

15. Extracting DNA from a Strawberry
Feel like a real-life Jurassic Park scientist when you show your classmates how to extract DNA from a strawberry.

16. Bottle Flip Challenge
There’s a little more than luck involved in the viral Bottle Flip Challenge. Students can learn to test for the variables of bottle size, shape, and water level in this project.

17. Show Off a Tooth Decay Model
Using eggshells and mason jars filled with various liquids, create this tooth decay model, explaining to your peers how various substances cause decay.

18. Floating Paperclip
Explore the concept of surface tension by making a paperclip float in a glass of water in this easy science fair project.

19. Make a Rainbow
It may have taken tons of experimentation for Isaac Newton to discover that there is a full-spectrum of color in every beam of light, but all your student needs is a prism and flashlight to demonstrate this rainbow phenomenon. 

Photos and video by the author