City University of New York
Lehman College: An Introduction to Lines
Use this site for two short lesson plans regarding Euclidean and Spherical lines. Intersecting and parallel lines are discussed. The lesson contains activities for two days of class.
University of Regina (Canada)
University of Regina: Math Central: Introduction to Slope for Middle Years Mathematics
This collection of five middle school math lessons covers the topic of plane geometry, specifically the concept of slope. The first lesson introduces students to plotting points on a Cartesian grid using a Geoboard. Lesson two moves them...
Illustrative Mathematics
Illustrative Mathematics: G Gpe, G Co, G Srt Unit Squares and Triangles
In this task, students are shown three unit squares and two line segments connecting two pairs of vertices. They are asked to find the area of a triangle formed by intersecting lines. They can solve it using coordinate geometry or...