8.G.A.5 Grade 8 · GeometryUse 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.Common Core State Standards for Mathematics, as adopted in the Massachusetts Curriculum Framework for Mathematics (2017), Grade 8.
Play the game: Anglesfree, no sign-up →Shapes are built, turned, cut and stacked, not just named. A square is an area you lay out yourself; a cube is that square stacked into layers.
Every page is free and open — nothing to install, no account, and it works on a phone or a classroom board. Every number has its own color: 1 red, 2 orange, 3 yellow, 4 green, 5 blue, 6 purple, 7 brown, 8 pink, 9 cyan, and a number is that many colored dots.
8.G.A.1Slide, turn and flip a shape; measure before and after: lengths, angles and parallel sides stay the same8.G.A.2Congruent: find the slides, turns and flips that put one shape exactly on another8.G.A.3Move shapes with coordinate rules: (x+3, y−2), (x, −y), (−y, x), (2x, 2y), and work back8.G.A.4Similar: moves plus a stretch; find the scale factor and the sequence8.G.B.6Pythagorean theorem and its converse: the four-triangle proof, and pouring two squares into the third8.G.B.7Use the Pythagorean theorem8.G.B.8Distance between two grid points: along and up are the legs, the distance is the long side8.G.C.9Volume of cones, cylinders and spheres: a cone is ⅓ of a cylinder, a sphere ⅔ColorMyMath · getridoftheteacher.com · every number has its own color, and a number is that many colored dots. Matching a game to a standard is a judgement call; the official text is at doe.mass.edu.