Color mixing bags: a mess-free 15-minute preschool science activity
What it is: a science activity where students squish two blobs of paint together inside a sealed bag and discover a new color. Students predict, observe and name what they see.
Time: about 15 minutes. Grade: Pre-K (ages 4 to 5).
Materials: zip-top bags, washable paint in red, yellow and blue, packing tape, and a sheet of white paper to put under each bag.
- Before class, put a spoonful of two colors in each bag at opposite corners. Squeeze out the air, close the bag and tape the top closed.
- Show a bag with yellow and blue. Ask: "What do you think will happen if we mix them?"
- Each student gets a bag on white paper and presses the colors together with their fingers.
- Students tell a partner what new color they made.
- Make a class chart: yellow plus blue makes green, red plus yellow makes orange, red plus blue makes purple.
- Students trade bags to try a different mix.
Safety: tape every bag closed and check it before handing it out. If a bag leaks, wash hands with soap and water.
Differentiation: students who need support start with one bag and you name the colors together. Students who are ready can predict before every bag. English learners can point to the color on the chart.
Quick check: hold up two paint colors and ask a student to say what color they will make.
Need it for another grade or subject? Ask us on the request page and our team will write it.
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About this resource
- Shared by
- @UpOnlyLearning · Curriculum team
- Posted
- Oct 30, 2026
- Type
- Lesson plan
- Grade
- Grades K–2
- Subject
- Science
- Language
- English
- License
- Free for classroom, co-op and tutoring use. Please don't resell.