This is definitely going to be a short post today. Also if there are more typos, poor grammar, or run-on sentences than my usual amount it’s because I’m tired and on cold medicine. I caught a cold over the weekend. Not a bad one, just enough of one to make me feel extra blergh. The worst of it was on Saturday and Sunday, but I still had some sinus and throat issues this morning. I popped some DayQuil and came to work. Several times I almost threw together sub plans and went home but I really didn’t want to take a day off in the first month.
I told the students that I would not be my normal animated self because of my cold. I had them work on a math journal (they didn’t take it to that idea yet, but I’ll get them going on it) and then a word problem while I came around and gave them access to the online textbook. It cracked me up today because a student asked me when we were going to use the textbook and I had assigned 5 problems out of the book just last week.
As an introduction to “solving for a given variable”, I asked the students to remind what the formula for the area of a rectangle was. Some blocks needed more prompting than others, but we all got there eventually. I was probably more helpful than I should have been, but I was sick and didn’t have a lot of energy for questioning them to the formula. Besides, the task wasn’t about just remembering the formula for area.
Once we had the area formula I told them that I wanted them to find as many rectangles with an area of 60 as possible in groups. I gave them 5 minutes to work on this and then asked them to write the rectangles they found on the board. (I also asked them to consider whether a 60 x 1 rectangle was any different from a 1 x 60 rectangle.) After they wrote what they found on the board, I went group by group and asked them:
“What strategies did you use for finding rectangles?”
I got answers such as:
- We put it in the calculator
- 12 x 5
- We just knew
- We put numbers in
- We divided
- 20 x 3. Just 20 x 3.
- We saw 20 x 3 so we did 3 x 20
- I knew 2×3 was 6 so I added a 0
- We didn’t find any
Obviously I had to help them elucidate these strategies through some questioning. I got a lot of answers of dimensions of rectangles rather than strategies to find the dimensions of rectangles from one block. The “game” just didn’t seem to click for them, even after I told several groups “Yes, that’s what you found, but HOW did you find those.” This block also had a lot of answers of “We just knew.” However another block latched on to dividing 60 by different numbers with no prompting or hints from me at all.
I like this task quite a bit and I wish a little bit that I had saved it for a day when I wasn’t sick and could have run it better. Oh well. As it was, I used it as a hook and transition into solving equations for a particular variable. I will probably come back to it if we do indirect variation.
That was the majority of my lesson other than the individual work that the students did. I can’t write anymore right now anyway, I feel a little dizzy. Gonna take a nap.