## Geometry

 Online Activities Worksheets
Lessons
Geometry Lesson Plans - Discovering Pi, Exploring the Sphere, Exploring Similarity Using Scale Drawings, Greedy Triangle, Measuring Circles, Measuring the Earth, Planning a School Garden, Plotting Coordinates on a Geoboard, Polygons, Tangrams, Three-Dimensional Shapes, Water to the Max, Web of Lines.
PBS Teachers: 9-12 Lessons - Great detailed lessons for Geometry & Spatial Sense that includes links to resources.
6-8 Lessons
Daily Lessons - Structured Curriculum Handbook: Reasoning & Proof, Parallel & Perpendicular Lines & Congruent Triangles to Exploring Quadrilaterals, Connecting Proportions & Similarity .
Geometry Resources - Text book-like instructions, examples & formulas: Trigonometry, Inversive, Coordinates, Inequalities, Sangaku Problems & more.
Formulas - Lines, Distances, Angles, Concurrence, Collinearity, Triangles, Quadrilaterals, Regular Polygons, Circles Conics, Cartesian, Cylindrical, Spherical, Rotation & Polar Coordinates, Cartesian Symmetries, Direction Angles & Cosines, Planes Regular Polyhedra, Cylinders, Cones, Spheres & Torus.

## Geometry

 Online Activities Worksheets
Lessons
AAA Math - Geometry Facts & Calculations, Area, Perimeter, Circumference, Surface Area, Volume, Cubes, Rectangular & Triangular Prisms, Cones, Cylinders, Spheres & Pyramids.
Cool Math - Online lessons & examples on: Polyhedra Gallery, Tessellations, Congruency, Interior Angles of Regular Polygons.
High School Lessons - Euclidean/Plane (proofs), Conic Sections/Circles (ellipses, parabolas, hyperbolas) Constructions, Coordinate Plane, Triangles, Polygons, Polyhedra (Platonic & Archimedean solids, prisms) Non-Euclidean, (elliptical/spherical, hyperbolic, projective), Symmetry & Tessellations.
Middle School Lessons - Two-Dimensional, ( area, perimeter, proofs), Conic Sections, Circles (ellipses, degrees, radians), Triangles, Polygons 3D & Higher, (volume, spheres, cylinders, cones) & Polyhedra (cubes, pyramids, prisms, nets).
Video & Text Lessons - Covers everything from Arcs & Chords, Area of Regular Polygons Law of Cosines & Sines to Linear Graphs, Special Quadrilaterals, Surface Area and Volume.
Trigonometry 