The coordinate plane is a two-dimensional surface on which we can plot points, lines and curves. It has two scales, called the x-axis and y-axis, at right angles to each other that meet at the point of origin (0, 0). Rather than teaching graphing equations using the coordinate plane in an abstract format, students are given real-life examples of how and why they could create and use a line to give them information that will help them to solve problems.
In the first lesson, students create a ramp and record both time and distance of miniature cars going down the ramp. They do this three times and find the average rate. They then interpolate other times and create a graph of the data.
The students follow a lemonade stand operation in the second lesson to determine what will make the stand successful. They use algebraic equations to help make that determination.
In the third lesson, students create a walking course and record the time and distance walked. They create a graph of their times and use an equation to find the rate.
Formative and summative assessments are available, as well as an overview of graphing linear equations and a vocabulary sheet.
Grade 8, Mathematics — Patterns, Functions and Algebra
D. Use algebraic representations, such as tables, graphs, expressions, functions and inequalities, to model and solve problem situations.
Y2003.CMA.S04.G08-10.BD.L08.I07 / Use Algebraic Representations
07. Use symbolic algebra (equations and inequalities), graphs and tables to represent situations and solve problems.
Y2003.CMA.S04.G08-10.BD.L08.I08 / Use Algebraic Representations
08. Write, simplify and evaluate algebraic expressions (including formulas) to generalize situations and solve problems.