Illustrative Mathematics K–5 · Grade 4 · Unit 8 · Properties of Two-dimensional Shapes
Welcome to the gallery! Sort the triangles, study the quadrilaterals, fold shapes in the hall of mirrors, and measure the frames. Then hang the pictures at the Grand Gallery. Each station matches lessons from class.
Each station deals 8 fresh problems (the Grand Gallery deals 10). A right answer on the first try earns 10 points. After a wrong answer, the game names the likely mistake and gives one more try for 5 points. At the Grand Gallery, each right answer hangs one of 10 pictures.
Hints point to the marks from class: tick marks on equal sides, right-angle boxes, and folding on a dashed line (the folded outline shows where the shape lands). A used hint caps that problem at 5 points.
Mixing up the names of triangles, counting parallel sides instead of pairs, missing the corner-to-corner lines of symmetry (or counting folds that don’t match), dividing a perimeter by the wrong number of sides, and adding sides of a figure that should be subtracted (or the other way).
Lengths are whole centimeters. An equilateral triangle counts as isosceles too, as in the unit: it has at least 2 equal sides.
Each station matches a chapter of the Learn page for this unit, which walks through the ideas step by step.
All Kinds of Attributes (Lesson 6), Symmetry in Action (Lesson 9), and Ways to Find Angle Measurements (Lesson 10) are optional lessons, so there are no stations for them.