Describe characteristics of basic shapes. Use basic shapes to compose and decompose other objects in various contexts.

Benchmarks1. Describe characteristics of two- and three-dimensional objects, such as triangles, squares, rectangles, circles, rectangular prisms, cylinders, cones and spheres.

ExamplesTriangles have three sides and cubes have eight vertices (corners).

2. Compose (combine) and decompose (take apart) two- and three-dimensional figures such as triangles, squares, rectangles, circles, rectangular prisms and cylinders.

Decompose a regular hexagon into 6 equilateral triangles; build prisms by stacking layers of cubes; compose an ice cream cone by combining a cone and half of a sphere.

Another example: Use a drawing program to find shapes that can be made with a rectangle and a triangle.



Use basic concepts of measurement in real-world and mathematical situations involving length, time and money.

Benchmarks

Examples
1. Measure the length of an object in terms of multiple copies of another object.

Measure a table by placing paper clips end-to-end and counting.
2. Tell time to the hour and half-hour.


3. Identify pennies, nickels and dimes; find the value of a group of these coins, up to one dollar.