Homemade Barometer

In my continuing effort to improve my performance as a homeschooling science teacher, the boys and I made a barometer.

It was quite simple, requiring only a straight sided jar, a ruler, a clear tube and some ABC gum.

(That's Already Been Chewed for those of you who were never a child.)

The making and using of the barometer was the easy part. Explaining atmospheric pressure was a whole 'nother thing.

In the end I found that so much explanation of the hows and whys of atmospheric pressure was not as important as simply using the barometer and seeing the correlation of its changes with the changes in the weather.

This was a good week to start since we are having the usual variable Oregon spring weather. Really any time in Oregon is a good time to observe a barometer. The weather changes from hour to hour sometimes. Weathermen here are challenged to make accurate predictions.

We've only been observing the barometer for three days and we've seen changes in it every day. The boys saw the measurement drop slightly from the first day which was simply overcast. Following the drop in pressure we had a day of steady rain and occasional snow flurries. That night Samuel announced the water level in the tube had increased and sure enough, the next morning we woke up to clear blue sky. These changes and correlations made the boys excited about continuing to use their barometer. They also want to get a real one for permanent use.

One thing I have learned is that the clear plastic tube we used for the instrument (I raided my fountain supplies in my studio) would work better if it was a smaller diameter. The water is only moving in 1/8 inch increments but would move more dramatically if the tube was smaller.

Other lessons that have come into our little scientific study include the use of record keeping for science or hobby and also a good vocabulary lesson. We talked about the Greek suffix "meter" in barometer, thermometer, odometer and speedometer.

All in all, a productive science week.