Maryland Math 8.AT.A.1

8.AT.A.1 is a cluster heading. These are the individual standards under it.

• 8.AT.A.1.a

  Graph proportional relationships and interpret the unit rate as the slope of the graph.

• 8.AT.A.1.b

  Compare proportional relationships represented in different forms (e.g., graphs, equations, and tables) by analyzing their slopes.

01

What Students Need to Do

Students graph proportional relationships as lines through (0, 0). They find each line’s slope as the rate for one unit and compare rates shown in tables, graphs, and equations.

02

What Mastery Looks Like

Given a table showing $12 for 3 pounds, a graph through (0, 0) and (2, 10), and the equation y = 3x, a student finds rates of $4, $5, and $3 per pound. They order the rates and explain what each slope means.

03

Common Misconceptions

Students may compare total amounts instead of rates per unit. They may use a point’s y-value as the slope without dividing by its x-value, or call a graph with a starting fee proportional.

04

How to Assess It

Exit ticket: One service costs $12 for 3 miles. Another follows y = 5x, where x is miles and y is dollars. Which costs more per mile, and by how much?

1. 01

   Plot (0, 0), (1, 2), and (3, 6) with counters on grid paper, then draw the line and mark the rise for one step right.

2. 02

   Show a table with (1, 4) and (2, 8) beside y = 3x; ask which rate is greater and how students know.

3. 03

   Give pairs table, equation, and same-scale graph cards; have them match equal unit rates and write the rate on each card.

4. 04

   Use grocery tags showing $6 for 2 pounds and $8 for 4 pounds; graph cost against pounds and compare the slopes.

• 7.AT.A.2

  Identify proportional relationships between quantities.

• 8.AT.A.2

  Use proportional reasoning to identify slope and represent linear relationships.