Your 4th graders will learn to classify triangles and quadrilaterals with these 12 polished, no-prep activities aligned to the Common Core. Sorting polygons by properties will engage your students in higher-order thinking. Watch their geometry skills blossom as they identify properties in 2d shapes: parallel, perpendicular, symmetry, acute angles, right angles, and obtuse angles. Geometric shapes include equilateral triangle, isosceles triangle, scalene triangle, right triangle, square, rectang