Draw points, lines, line segments, rays, angles (right, acute, obtuse), and perpendicular and parallel lines. Identify these in two-dimensional figures.
Classify two-dimensional figures based on the presence or absence of parallel or perpendicular lines, or the presence or absence of angles of a specified size. Recognize right triangles as a category, and identify right triangles.
Recognize a line of symmetry for a two-dimensional figure as a line across the figure such that the figure can be folded along the line into matching parts. Identify line-symmetric figures and draw lines of symmetry.
Use facts about supplementary, complementary, vertical, and adjacent angles in a multi-step problem to write and solve simple equations for an unknown angle in a figure.
Use informal arguments to establish facts about the angle sum and exterior angle of triangles, about the angles created when parallel lines are cut by a transversal, and the angle-angle criterion for similarity of triangles. For example, arrange three copies of the same triangle so that the sum of the three angles appears to form a line, and give an argument in terms of transversals why this is so.
Grade: 09, 10, 11, 12
Know precise definitions of angle, circle, perpendicular line, parallel line, and line segment, based on the undefined notions of point, line, distance along a line, and distance around a circular arc.
Grade: 09, 10, 11, 12
Identify and describe relationships among inscribed angles, radii, and chords. Include the relationship between central, inscribed, and circumscribed angles; inscribed angles on a diameter are right angles; the radius of a circle is perpendicular to the tangent where the radius intersects the circle.
In this math game, students control a tiny robotic spider named Itzi, who lives with his family at the top of a strange old grandfather clock. On each level Itzi must find a safe path through an intricate maze of tangled webs, solving cunning angle puzzles as he goes. Students' ultimate goal is to guide Itzi safely to the Warp Gate by applying their understanding of geometry concepts to various challenges. Note that students will not control Itzi’s movement directly, but will instead rotate the giant cog to make Itzi roll according to gravity. This aspect of game play enables students to explore angles, parallel lines, polygons, triangles, circles, and more.
In this lesson plan adaptable for grades 3 through 8, students use BrainPOP resources (including an interactive game) to learn about basic geometry concepts. Students will explore angles, parallel lines, polygons, triangles, circles, and more while applying their findings to real-life situations. This lesson plan is aligned to Common Core State Standards. See more »