Use Bubbles—Observe Wind Speed and Direction: Ask a Question and Plan an Experiment

If you can’t see wind, then how can you tell its speed or direction? Meteorologists depend on wind features to forecast the weather. They use tools, such as weather vanes, to determine wind direction and anemometers to measure wind speed.

While they can’t see wind, students can observe what it does to things around them, such as blowing their hair, moving tree limbs, or crackling flags. Meteorologists use the Beaufort scale to estimate wind speed. Scientists designed this scale based on the movement of flags, trees, and smoke.

In this activity, students make direct observations using bubbles to measure and describe wind speed and direction. They use appropriate vocabulary (e.g., calm, breezy, and windy) during class discussions to describe their observations about wind conditions.

Note: As the students work with bubbles to make observations about wind, they may ask, “Why does my bubble pop?” The most common reason is contact with a dry surface.

When students experiment with bubbles outside, the bubbles evaporate quickly. This is why one partner blows the bubble while the other partner observes the location where the bubble pops, moves to that position, and stands there. This allows the first partner to pace the distance the bubble traveled. When there is strong wind, or even a gentle breeze, bubbles are much more difficult to create and inevitably pop due to the wind’s force. If you are in a dry climate or if a bubble touches a dry finger, blade of grass, or concrete, it will pop instantly.