Materials
- A button
- A pencil
- A marble
- A metal spoon
- A plastic fork
- A sponge
- A toothpick
- A small rock
- A metal bottle cap
- Anything else you want to experiment with
Testing Data Sheet or Blank Testing Data Sheet (print these out or make your own versions!)
Directions
- Find a spot (inside or outside) where you can make a wet mess.
- Fill a small container with water (use a clear container if you have one) or fill the kitchen sink half-way with water and use a chair or stool so you can comfortably reach the sink
- Collect objects from around your house (see above list for suggestions)
- Look at the materials you will be testing and guess which objects will sink or float. Why did you make that guess?
- Place the objects in the water one at a time. What happens? Which items sink and which items float?
- After observing each item, physically sort them into two piles based on whether the items sink or float. Or record your data by writing or drawing a picture of the object on pieces of paper labeled “Sink” and “Float”. You can use the Testing Data Sheet to record your predictions and results.
- Do you notice anything that is similar about the things that float? What about the things that sink?
- Keep Exploring! Can you change the features of some of the objects to change the results? Use a rubber band and attach some of the items that sink to items that float. Now what happens?
You can also download and print:
Sink and Float Activity Directions and Helpful Hints (English PDF)
Sink and Float Activity Directions and Helpful Hints (Spanish PDF)