Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in two-dimensional figures.
In this concept attainment lesson, students try to determine if lines are perpendicular or not
Why tell a kid the rules of a triangle when they can discover them!?
Can you find perpendicular and parallel lines in a work of art?
A lesson about lines, line segments, and rays that avoids dull memorization. Instead, we ponder this delightful question: Which is longer, a ray or a line? Then, kids consider what these different geometric concepts would think about each other.