The big new idea of this lesson is to treat linear data tables as distance vs. time data tables. In some ways, this lesson is asking students to move from the more concrete examples of tile patterns to more abstract data tables. One way that this shift is challenging for students is that in the case of the tile patterns, students were always able to see consecutive entries in the patterns. The consecutive patterns made it very easy to determine whether a pattern was linear and if it was, it was also very easy to identify the growth rate. In the data tables provided today, there are many missing entries and the entries provided are not consecutive. This requires students to develop a more abstract understanding of how linear growth rates work.
In closing, I like to remind students that these problems are exactly the same as what they already know, and their only challenge is to figure out how to turn these problems into the problem that they already know how to solve.
The actual closing questions ask students to use the key terms of the lesson to describe a problem. As much as possible, I like to have students explain whatever they do understand, even if it is not thorough understanding, because I want the exit tickets to begin a dialogue with individual students about the big ideas. If there is too much scaffolding, then I don't get a picture of their individual understanding.