Math Slice
Math Slice: Graph Slice Special Test
A ten question test for assessing measurement concepts of area and perimeter. Assessment is scored online and student scores are compared with other students who have taken the assessment. Great assessment tool.
Shodor Education Foundation
Shodor Interactivate: Lesson: Lines, Rays, Line Segments, & Planes
This robust lesson plan for upper elementary and middle school grades introduces the concepts for lines, rays, line segments, and planes. Resources are linked to it and ready for your use.