SWBAT solve problems involving points, lines and polygons on the coordinate plane

A polygon is made up of line segments that connect the shapeâs vertices. The vertices can be identified as unique points on a grid.

5 minutes

Students work in pairs on the Think About It problem. After 3 minutes of work time, the class comes back together. First, I ask students to vote with their thumbs about whether Angel is right or wrong. If a number of students show me thumbs up, it tells me that students are confusing area and perimeter, and that I'll need to review these concepts before partner practice and independent practice. I then have 2-3 students share out their written responses to this problem and offer in-the-moment feedback on what I like and what would make their responses stronger.

12 minutes

I use the Intro to New Material problems here as a guided practice. I want to give students a chance to review the geometry vocabulary with me before they work independently. Words/concepts that are important for students to access in this lesson: perimeter, area, right triangle, vertex, vertices, isosceles.

15 minutes

Students work in pairs on the Partner Practice problems. As students work, I circulate around the room. I am looking for:

- Are students correctly plotting the coordinate pair on the grid and labeling them?
- Are students correctly determining the distance of two points on the grid?
- Are students accurately determining perimeter?
- Are they showing their computation?
- Are students correctly creating shapes on the grid given certain parameters?
- Are students correctly identifying the shapes that they plot?

I'm asking:

- How did you know to draw the coordinate pair in that particular place?
- How did you determine how far one point was from the other?
- How/when could you determine the distance between two points in different quadrants?
- How did you determine the perimeter?
- What errors might a scholar make when calculating perimeter?
- What's the name of that shape? How is that different from a ___ (another similar shape)?
- Which quadrant is this?

After 10 minutes of partner work time, students complete the check for understanding problem on their own. Students have 3 minutes to work on this. I then have students show me the quadrant number for each of the plotted points. I cold call on one student to give the ordered pair for the 4th vertex. I cold call a second student to agree or disagree with the ordered pair (and provide justification).

12 minutes

Students work on the Independent Practice problem set. As I circulate, I am looking for and asking the same questions that I used in the Partner Practice section.

- Are students correctly plotting the coordinate pair on the grid and labeling them?
- Are students correctly determining the distance of two points on the grid?
- Are students accurately determining perimeter?
- Are they showing their computation?
- Are students correctly creating shapes on the grid given certain parameters?
- Are students correctly identifying the shapes that they plot?

I'm asking:

- How did you know to draw the coordinate pair in that particular place?
- How did you determine how far one point was from the other?
- How/when could you determine the distance between two points in different quadrants?
- How did you determine the perimeter?
- What errors might a scholar make when calculating perimeter?
- What's the name of that shape? How is that different from a ___ (another similar shape)?
- Which quadrant is this?

10 minutes

After independent practice, we come back together as a class. I have one student share out the answer to Problem_13. I then have students turn and talk about their responses to Problem 14. I have 1-2 students share out their thoughts. I want them to come to the realization that the perimeter will increase by 4 units in this situation, so I ask questions until they come to that conclusion. I push them to model with a picture.

Students then work independently on the Exit Ticket to end the lesson.

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