Did the carrot float or sink? Take a teaspoon of salt and put it in the water ... when the density of the water is very similar to the density of the carrot. The materials in this activity are not ...

Did you ever wonder why hot air balloons float? You may already have some ideas. Think about them and then choose one of the options below that seems closest to why you think balloons float.

Students put objects and materials into groups based on their observable properties, test materials for strength and absorbency, and use their results to make a boat that can hold the most pennies ...