Each day, students complete a warm-up that usually consists of spiraling the previous day's material, in addition to older material. Warm-up problems also sometimes extend lessons that students have encountered before to more unfamiliar contexts.
In this lesson, #3 provided a particularly rich learning activity.
A rectangle has a height that is five less than triple the base, b. Which of the following shows the perimeter of this rectangle?
Most students who chose the wrong answer chose "3b - 5." This provided a chance to talk about:
- close reading of the problem
- using a diagram to model a situation
- collecting like terms, including with negative numbers.
A task that has a bit of a "gotcha" element tends to stay in kids' minds longer, as long as there is a memorable and understood "aha" moment, which this task has. I love using this as a warm-up problem, particularly as the last problem.
The homework includes questions related to this lesson, as well as spiraled review. I also provide answers to the problems on page 2.