# Oni's Equation Adventure- Day 10

## Objective

SWBAT solve systems of linear equations in two variables algebraically using substitution.

#### Big Idea

Now that students understand how to use substitution to solve systems, they must analyze Oni's work for errors.

## Warm Up

8 minutes

For today's Warm Up assignment, I have selected two linear systems for students to solve using the substitution strategy. I want to ensure that students are comfortable with the strategy as they will be expected to work at applying it at the analysis level today. As students work, I move throughout the tables taking notes on my observation clipboard. I make note of students who finish efficiently as well as those who struggle. This will provide important information for me later in the week when I group students.

Once the timer sounds after 5 minutes, I bring students' attention to the Smartboard and select students at random from the cup of names to provide their answers. I then ask for class agreement and work toward it through questioning, if necessary.

Once consensus is reached, I move to today's learning objective.

## Learning Objective

3 minutes

At the close of Warm Up, I introduce today's Learning Objective. I want students to understand that we are continuing our work with substitution, just at a higher cognitive level today. I quickly solve the system that is displayed, intentionally making an error. If a student notices, I ask him/her to come to the board and highlight the line where I made the error. I then ask him/her to take on the role of teacher and ask one question that might help me get back on track with my work. I record their question on the board. I then explain that we have just modeled the expectations of today's Work Time session.

## Work Time

25 minutes

I reveal the Work Time instructions and ask a volunteer to read while I distribute copies of Onis Work and highlighters. I ask a volunteer to recode the directions in their own words so that students get a third explanation of my expectations. I supply and needed clarifications, set the timer for 25 minutes and encourage students to begin looking for Oni's mistakes.

When the timer sounds, I bring the group back together for consensus building.

## Building Consensus

9 minutes

Once I have the students' attention, I call on a pre-selected student to share the line she highlighted on the first problem. I then ask her to share the question she wrote for Oni to get her back on track. I want all students to be exposed to strong questions that reveal and correct common misconceptions. I then model a poor question and ask the students which question would better help a student get back on track. We continue in this manner with the remaining five problems.

It is my intent with this exercise to help students not only evaluate the work of other student (MP3), but also to begin to ask these types of questions of themselves as they work.