The [water tank video] is simply boring. I do not think middle school students would sit and be engaged throughout the entire video. [..] All we know is that someone is filling the tank; we don't know its shape or dimensions, we don't know the rate of the water flow, and, in the end, we don't care. The video is too long and, quite frankly, uninteresting. I couldn't watch the whole video (although I left it playing to listen for any changes) and I certainly can't see a group of middle schoolers watching and being engaged.
This response gave me a good angle on three return volleys:
- What if we decided not to show the entire video? What could we do with that?
- The student mentioned that "we don't know its shape or dimensions, we don't know the rate of the water flow …." Do you realize how much conceptual skill that critique requires? How many of your students can answer the question, "What do you need to know in order to solve this problem?"
That third bullet is a response to a wager I made back in February:
Twenty seconds into watching the hose dribble water into the tank, ask "how long do you think this is gonna take?" Ask [your students] for guesses. Just guesses. Write them on the board next to the guessers' names. Whenever anyone raises the maximum or lowers the minimum, point it out. Then turn the clip off. Turn off the projector and proceed to whatever else you had planned for the period.
I wagered that students would riot. I found the whole classroom anecdote worthwhile, but here's the vindicating part:
After the students made their predictions, I abandoned the water tank problem and moved on to something completely different. In each one of my classes, eventually a few of the students made a comment along the lines of “you never told us how long it took to fill the tank.” Sometimes the comment came only a few minutes after we had moved on. Other times, it came much later. More convincing evidence of the students’ level of engagement in the exercise came at the end of the lesson when I played the rest of the video. With their focus on the screen, you would have thought they were watching a summer blockbuster at the movie theater, not a tank filling with water in a classroom.