Science worksheet · Sink or float
Sink or Float: Predict and Test
Guess whether eight objects will sink or float, test them in a tub of water and check your guesses.
- Grade level
- Grades K–2
- Time
- About 20 minutes
- Topic
- Sink or float
- Answer key
- Not needed: answers vary
- Kids practice
- Sinking and floating, Density, Predicting and testing
What kids do
Printed on the sheet:
- Do it: fill a tub with water. Guess first, then gently set each object on the water and watch.
- My guess: sink or float?
- How many did you guess right?
Words on this sheet
Objecta coina leafa corka rocka spongea spoona toy blockan applesinkfloat
Teacher tip
Use a clear tub so everyone can see.
How to use it
- Set up a water tub with towels and let kids test real objects.
- Ask kids to predict and record before every test.
- Start with a two-minute “I notice, I wonder” talk about the picture on the sheet.
Watch for
Big things don’t always sink. Shape and material matter.
Talk about it
- Why does a heavy ship float?
- What did you notice that surprised you?
Take it further
Hold a boat-building contest with foil and pennies.
US Letter, prints well in black and white. Free for home and classroom use: print as many copies as you need.
More sink or float worksheets
Grades 2–5
Clay Boat Challenge
An engineering challenge: shape clay into a boat that floats and holds as many pennies as it can.
Grades 1–3
Floating: True or False?
Seven facts about sinking and floating to mark true or false, then explain how a heavy ship floats.
Grades 3–5
Liquid Density Tower
Pour honey, dish soap, water and oil into a cup, number the layers from bottom to top and draw your tower.
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