Sink or Float? – A Simple Science Experiment for Curious Preschoolers

16 hours ago
2 min read

At Ducklings Preschool, we believe every child is a little scientist — naturally curious, full of questions, and eager to explore how the world works.This week’s hands-on investigation invites your child to become a Water Explorer with our Sink or Float Experiment — a fun and easy way to introduce early science, STEM, and critical thinking through play.

And the best part? We’ve created a free printable Sink or Float activity sheet that families can download, print, and try at home — no membership required!

💧 What You’ll Need

All you need are some everyday household items, a bowl or tub of water and a towel (for spills). Our free downloadable sheet includes pictures and tick boxes for the following objects:

✏️ Pencil
🧷 Paper clip
🗒️ Notecard
☁️ Marshmallow
🚗 Toy car
💰 Coin
🪵 Cork
🖍️ Crayon
🍃 Leaf

Click here to download and print off our Sink or Float Predictions Checklist

Sink or Float Prediction Experiment Sheet

🧠 How to Do the Experiment

Predict: Look at each item together and ask, “Do you think it will sink or float?”
Test: Drop one object at a time into the water.
Observe: Watch closely — does it sink to the bottom or float on top?
Record: Use the sheet to tick or colour in each object’s result.
Discuss: Ask, “What do you notice?” and “Why do you think that happened?”

There’s no rush — repeat, mix it up, or swap in new objects as your child gets the hang of it. Focus on step 5, discuss. This step is where this activity is more valuable! Although it might look like a simple game, the Sink or Float activity supports several key areas of development for children aged 2–5 years:

Scientific Thinking

Children observe, predict, test, and reflect — just like real scientists! They begin to understand cause and effect and notice patterns (heavy things often sink, light things float).