Science teacher Elizabeth Kaplan sometimes takes her seventh-grade enrichment class to the Charles River during fifth period.

Sometimes it’s too cold to walk, or someone forgets their jacket. On one trip in January, it was freezing, winter jacket or not. In a 42-minute period, 28 minutes were spent walking to and from the river.

While at the river, the students stood on a wooden landing above the frozen river. The students had to crack ice (that they couldn’t reach because of the railing) with a white plastic bucket on a rope, and then collect some water in the bucket. They then lifted the bucket from the river and put it on the ground.

Some students stood back and observed, while others took test tubes and put a measured amount of water in them and tested the pH level. The pH is measured from 0 (basic) to 14 (acidic), with a good result, according to Ms. Kaplan, being somewhere in the middle.

The students with the test tubes on this trip came up with a 7.4 in their water sample, which was a good result.

–March 4, 2010–

(Testing the Charles River’s water — in the middle of winter! from the Watertown Splash on Vimeo .)