Working Backwards with Formulas

Why this lesson is awesome! It’s more fun to go in reverse, just ask Mater! This lesson requires students to manipulate formulas to solve for unknown values.

Section #1: Overview
Objective: Students will set up equations using known area formulas to determine measurements of unknown dimensions.

Extensions and Scaffolds: This lesson is intended for all learners in the classroom. Examples range in difficulty from solving a one-step equation, to having to take the square root of a number.
Environment for this lesson: Students are seated in homogeneous groups of 3 or 4 at tables. Grouping is based on level of understanding as shown in the previous lessons.
Tools and Instructional Technology or Software: Smartboard, Smart Clickers

Section #2: Launch
Indicated Time Allotment: 5-10 minutes

Section Narrative:

As students enter the room, they will immediately begin working on the opener (Resource: Working Backwards with Formulas Opener). The opener is a mixture of previously learned questions, and students should work individually, and then as table groups to discuss the methods for solving the questions. After approximately 5 minutes, I will call on students to go to the board and solve the opener questions.

After completion of the opener, I will address the day’s learning targets to the students. In today’s lesson, the intended target is, “I can determine unknown dimensions when given the area or circumference of a known figure.”

Resources: Working Backwards with Formulas Opener

Section #3: Explore
Indicated time allotment: 25-30 minutes

Section Narrative:

I will begin the lesson by passing out the notes sheet (Resource: Working Backwards with Formulas Notes, and Working Backwards with Formulas Smartboard), and drawing their attention to the first example problem. The first example is a basic formula, and should pull from their prior knowledge of working with formulas in 6^th grade. I will ask that students discuss the question with their table groups, and raise their hand to share out only when they can share an equation – not just an answer. During their discussion, I will walk around the room to hear the various conversations taking place. I will take a volunteer to come to the board to work out the first example, and then I will ask that they discuss the next example, following the same procedures they used in the first example. I again will monitor progress by listening in on table conversations, and will ask for another volunteer to work out the second example. Following the second example, I will ask that tables work together to complete the remaining five example exercises – using their knowledge from the first two examples to guide them. I will set the timer for 8 minutes, and then I will call on tables to work and verbally explain the problems at the board.

Resources: Working Backwards with Formulas Notes, Working Backwards with Formulas Smartboard

Section #4: Summarize

Indicated time allotment: 20 minutes

Section Narrative: Video Clip: Working Backwards Summary

As a way to assess student progress with the concepts learned this week, I will conduct a table challenge using the Smart Clickers (Resource: Working Backwards with Formulas Smartboard). At the conclusion of the activity I will reward the top scoring group(s). Students will be regrouped for tomorrow’s lesson based on results and teacher observation during the clicker activity.

After the clickers, I will summarize the lesson by posing the question, “How can I find unknown side lengths when given the area or circumference of a figure?” We will discuss as a group.

Resources: Working Backwards with Formulas Smartboard