Beginner
30 mins
Teacher/Student led
Learning Goals
Learning Outcomes
Lesson Files
+70 XP
Teacher-led from the board — pupils need no device

Float or Sink?

Explore floating and sinking by making predictions about everyday objects and testing them in water. Sort items into groups based on observations and record findings in an investigation journal. Hands-on activities help understand these basic science ideas.

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    Float or sink
    Ste exploration
    Observation

    1 - Getting Started ~3 mins

    The two objects the class will guess about, shown plainly and closeLook at this toy boat and this stone. If we pop them in water, which one will stay on top? Which one will go down?

    Hands up for your guess!

    👇 Mark your steps as done as you complete them.

    +5 XP

    2 - Float and Sink ~2 mins

    Side view showing one object on top, one on the bottom: float and sinkFloat means it stays on top.

    Sink means it goes down.

    We will guess first, then watch.

    👇 Mark your steps as done as you complete them.

    +10 XP

    3 - Guess on the Board ~3 mins

    You will see five everyday things on the board, and for each one we say float or sink out loud before anything goes anywhere near the water.

    Your guesses stay up on the screen, so later we can look back and see what the water really did.

    Will it float or sink?

    +15 XP

    4 - Water Tray Play ~8 mins

    Sleeves up! At the water tray we try our things one at a time.

    Put it in gently. Watch. Does it stay on top or go down?

    +15 XP

    5 - Watch What the Water Did ~3 mins

    Results grouped by what stayed on top and what went to the bottomLook back at our board guesses. What did the water really do?

    Which things stayed on top? Which went down?

    +15 XP
    Pupil practice · Investigation Journal
    Module 3 · Energy and Forces: What Makes Things Go, Pushes and Pulls, and Magnets
    Lesson 21 · Float or Sink?
    Download Investigation Journal sheet (PDF)
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