Objective: Identify 10 more, 10 less, 1 more, and 1 less than a two-digit number.
Students use materials and drawings to find 10 more, 10 less, 1 more, and 1 less than a given number (1.NBT.5). In Lesson 5, students use the familiar linking cubes (organized into tens) and 5-group columns. They engage in conversation about patterns they observe, “I see that 10 less than 34 is just 1 less ten, so it must be 24!” Students represent how the number changed using arrow notation, or the arrow way, as shown to the right.
There may be cases when our downloadable resources contain hyperlinks to other websites. These hyperlinks lead to websites published or operated by third parties. UnboundEd and EngageNY are not responsible for the content, availability, or privacy policies of these websites.