I introduced the concept of open number lines today. Basically, an open number line is a completely blank number line. Our focus was to "navigate" on a number line. To begin, I gave the students two numbers, an "I have" and "I wish I had". Using any strategy they wanted, they were to begin with what they had and move to what they wished they had.
For example, I gave the students the following:
- I have 17
- I wish I had 24
I asked them to place the 17 on the number line and show me how they would get to 24. Invariably, they would start with 17 and use seven tick marks to get to 24 (see below).
I asked them to think about this in a different way. What if we "jumped" to friendly numbers (the nearest 5 or 10) to keep us from having to make all those tick marks (see above).
From there we experimented with a variety of "I have" but "I wish I had" statements in an effort to become more comfortable working with open number lines. I also wanted them to understand the strategy of "jumping to friendly numbers."
To finish our day, we created a foldable about interpreting remainders called "What do I do with a remainder?". We ran out of time before we could put our notes to any use!