Math Field Trip... to the Beach!!!

Finally, I found a way to combine math with another subject! While studying ancient Greece, Casia learned about a mathematician named Thales. He figured out the height of a pyramid using its shadow. So Casia, Garrett and I took a field trip to the beach where there are plenty of tall buildings casting shadows onto the sand. 

We got there a bit late in the day and some of the buildings were already casting shadows down to the water. So we ended up picking a shorter building that would be easier to measure. We found a nice little historic look-out tower.

Casia put Garrett to work holding the other end of the tape measure. It was only 30' long,  so we had to keep moving it down the shadow (plus we had to be careful not to block the boardwalk).

Here's Casia measuring to the end of the tower shadow.

Casia measured Garrett's height to use in the proportion.

Then she measured his shadow.

Casia sat down with her notebook to calculate the height of the tower.  She figured it to be 49 3/4 feet.

Having figured out the height, we went into the historic building hoping they would be able to confirm it for us. Unfortunately, they didn't know how tall it is, but I left my email with them and they said they would try to find out. They were very nice and a gentleman there offered to take a picture of all three of us.












Update: I heard back from the museum of the Old Coast Guard Station and was told that the height from the ground floor to the top of the tower is 48 feet. So Casia's measure was pretty close! I consider this a very successful (and fun!) experiment.