Make a Hygrometer to Measure Humidity – STEM activity

Does your hair go frizzy during "April showers," when the weather turns damp? Strands of hair can relax and lengthen when the humidity (or the amount of water vapor in the air) increases, and then contract again when the humidity decreases. In fact, the rate of change in the length of hair strands is so dependable that they can actually be used as the basis for a hygrometer, a device that measures the humidity level in the air. Read more

What do a crazy hair day, a wooden door stuck in its frame, and the weather have in common? Humidity! In this fun hands-on weather lesson students explore surprising information about human hair, the air around them, and the weather by building a hygrometer from a strand of hair, a straw, a wooden panel, and two nails. A great way to make humidity visible! Read more