Simple Science: Will it Sink or Float? - The Chirping Moms - Free Printable

This worksheet is designed for a simple science experiment to teach children about density and buoyancy — the principles that determine whether an object will sink or float in water.

The core idea is:
* An object will float if it is *less dense* than water (it displaces a volume of water that weighs more than the object itself).
* An object will sink if it is *more dense* than water (its own weight is greater than the weight of the water it displaces).

Here is the prediction for each object, based on common materials and their density relative to water:

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Predictions: Will it Sink or Float?

| Name of Object: | FLOAT | SINK |
| :--- | :--- | :--- |
| Crayon | ✔ FLOAT | |
| Pencil | ✔ FLOAT | |
| Coin | | ✔ SINK |
| Popsicle Stick | ✔ FLOAT | |
| Toy Car | | ✔ SINK *(Assuming plastic/metal)* |
| Cotton Ball | ✔ FLOAT *(Initially, until saturated)* | |
| Marshmallow | ✔ FLOAT | |

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Explanation for Each Prediction:

1. Crayon: Made of wax, which is less dense than water. It will float.
2. Pencil: Typically made of wood (less dense than water) with a small amount of graphite and metal. The overall density is low enough to float, often horizontally.
3. Coin: Made of metal (like copper, zinc, or nickel), which is much denser than water. It will sink immediately.
4. Popsicle Stick: Made of thin, dry wood, which is less dense than water. It will float.
5. Toy Car: Most toy cars are made of plastic or have metal parts. Even if plastic, they are often solid and dense, or have heavy components like wheels. They usually sink. *(Note: A very light, hollow plastic car might float, but most standard toy cars sink).*
6. Cotton Ball: Made of air-filled fibers. It’s very light and traps air, making it less dense than water. It will float initially. However, once it absorbs water and becomes saturated, it may eventually sink.
7. Marshmallow: Contains lots of trapped air bubbles, making it very light for its size. Its density is much lower than water, so it will float.

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How to Use This Worksheet:

1. Make Predictions: Have the child check or mark "FLOAT" or "SINK" for each item before testing.
2. Conduct the Experiment: Fill a clear container with water. Gently place each object in the water one by one.
3. Observe & Record: Watch what happens and mark the correct column ("FLOAT" or "SINK") based on the actual result.
4. Discuss: Talk about why some things floated and others sank. Relate it to how heavy something feels for its size (density).

This activity encourages scientific thinking, observation, and understanding of basic physical properties!