Clip 1/7: Standard 4: Model with Mathematics Using Base Ten Part 2

Mathematically proficient students can apply the mathematics they know to solve problems arising in everyday life, society, and the workplace. In early grades, this might be as simple as writing an addition equation to describe a situation... They routinely interpret their mathematical results in the context of the situation and reflect on whether the results make sense, possibly improving the model if it has not served its purpose.

Liz O'Neill works with her first grade students engaging them in composing and decomposing numbers within twenty. Her students play a game called "How Many are Hiding?" Pairs are given a bag with 10 cubes, a paper plate, and the "How Many Are Hiding Recording Sheet." One partner takes some of the cubes and "hides" them under the plate. The remaining are placed on the top. The second partner uses sentence frames to answer the questions "What number do you see?", "How many are hiding?", "How do you know __ are hiding"? In addition, the answers are recorded. Roles are then reversed. The partner game gives students practice in composing and decomposing numbers within ten. Students who have completed the original task are challenged with changing the total number of cubes to 15 or 20.

See this video in the context of an entire lesson.

(Parts 2-4)