In this fully scripted, 2 segment, 2 hour lesson, 1st grade students will practice understanding that the 2 digits of a 2 digit number represent amounts of tens and ones and mentally find 10 less or 10 more than a number without counting.
In Segment 1, students will look for patterns on a number grid and collaboratively discuss how place value can help find 10 more or 10 less than a number without counting using color-coding on a number grid. Also, they will explain their reasoning on how they find 10 more or 10 less than a number and determine missing numbers by using the 10's strategy.
In segment 2, playing the game, Spin, Add or Subtract 10 collaboratively in partners, 1st graders will demonstrate their understanding of number sense for this standard.
Each segment has an exit slip that will provide valuable instructional information to you regarding your students understanding of place value for 2 digit numbers as well as the mental math skills that help determine a number without actually counting.