standard_description: Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.
problem_activity: Stage 1: Nearest Ten or Hundred
Required Preparation
Materials to Gather
Colored pencils, crayons, or markers
Number cards 0–10
Paper clips
Materials to Copy
Blackline Masters
Tic Tac Round Stage 1 Gameboard
Tic Tac Round Stage 1 Spinner

Narrative
Students remove the cards that show 10 before they start. Then they choose three number cards and make a three-digit number. They spin the spinner to get a place value to round to. Students write their number in any space on the board, each partner using a different color. The first player to get three in a row wins.


aligns: no