For today's Warm Up, I wanted to specifically address the students' ability to compare two functions given different representations (8.F.A.2). I presented the table of data for one animal and the graph of another and asked, "Based on the representations below, which animal was traveling at a faster rate?" I intentionally included a "head start" in the data table, which forced students to reason mathematically (MP 2). To move thinking along, I encouraged students to write what they knew from the information provided. I also reminded them to think about applying the other parts of the Rule of 5 in order to compare.
When the timer sounded, I selected volunteers to share answers and explain their thinking. One student shared a graph of Zebra's data, which showed it traveling at 5 hm/min. Another student shared a table of Antelope's data that showed it at 12 hm after 3 minutes. He compared that to Zebra at 19 hm after 3 min to determine Zebra traveled faster.
After Warm Up, I introduced students to the Rule of 5 Poster Project. Building on what we had learned over the previous lessons, I explained that I wanted students to create a story of their own that represented two linear functions. I then wanted them to create the related pictures, tables, equations and graphs.
After I introduced the project, I then shared the scoring rubric I would use to grade the projects once they were turned in two days later. I shared not only what a "Level 4" Poster would look like, but I also noted what might be missing that would cause the poster to score a "3", "2", or "1" on the rubric.
To help jump-start student creativity, I then guided a brief brainstorming session about story ideas. Students volunteered ideas such as comparing two phone companies, comparing two pizza restaurants, comparing two plumbing companies, and comparing two planes flying. I reminded students that a "level 4" poster had a new story, not a rehash of previous lessons or assignments.
I then explained that I would give poster paper to students once I approved their stories. This is a huge opportunity to catch and fix misconceptions. After reading their stories, I typically ask students questions like, "So how are you going to fit that on your graph?" or "So which company is going to cost less?". I have found that by previewing the stories with students and asking these questions, the rest of the project is much easier for the student to complete.
I handed out copies of the rubric and encouraged students to begin writing their stories.
Once I approve their stories, I encourage them to apply the Rule of 5 in their journals as a rough draft. That way, they can anticipate challenges (like scaling) when setting up their final poster.