Stories from the Classroom

Slopes and equations with Grade 9 students

Contributed by: ML Thompson, KCVI;
Nathalie Sinclair, Queen's

The Setting: November 2nd at the Computer Lab at KCVI in Kingston, Ontario. There are 24 PCs. ML had just completed a unit with her students on slopes, parallel and perpendicular lines, and equations of lines. The students were to write their unit test the following day so ML wanted to use this period with Sketchpad in order to review concepts covered during the unit. None of the students have used Sketchpad before.

Principles of Mathematics, Grade 9, Academic (MPM1D)
  • Analytic Geometry
    • identify the properties of the slopes of line segments (e.g., direction, positive or negative rate of change, steepness, parallelism, perpendicularity) through investigations facilitated by graphing technology, where appropriate.
  • Investigating Geometric Relationships
    • pose questions about geometric relationships, test them, and communicate the findings, using appropriate language and mathematical forms (e.g., written explanations, diagrams, formulas, tables);
    • confirm a statement about the relationships between geometric properties by illustrating the statement with examples, or deny the statement on the basis of a counter-example (e.g., confirm or deny the following statement: If a quadrilateral has perpendicular diagonals, then it is a square).

Day 1: