1. Unit of Study: Comparing Numbers Global Concept Guide: 3 of 3
10 Less, 10 More
Unit of Study: Comparing Numbers
Global Concept Guide: 3 of 3

2. Content Development

3. Day 1
Building Conceptual Knowledge – Voyages Grade 1 Excursions To 100 TE p
Introduce the lesson with the Setting the Stage section using the student p. 141
Continue with Building Conceptual Knowledge – Using the Hundreds Chart to Add and Subtract and Adding and Subtracting 10
Focus the lesson on seeing the patterns on the hundreds chart rather than on the addition and subtraction of the numbers.
End the lesson at the top of p. 92 in the TE, before Add and Subtract 20.
Exit Ticket – Hundreds Chart
Students show what they know about 10 more and 10 less on a hundreds chart by filling in missing numbers

4. Day 2 Building Conceptual Knowledge – Go Math Lesson 7.5
Each student uses base-10 blocks (rods and unit cubes) model and solve the riddle.
Make up additional riddles for students to solve on white boards or in math notebooks
Facilitate discussion to allow the students to make the connection that only the tens place changes when counting 10 more or 10 less
Discuss the term “mental math”
Independent Practice – Go Math Lesson 7.5 #9 – 16 on p. 307 and #19 & 20 on p. 308
Encourage students to complete these problems mentally
Ask them questions about their thinking to assess their understanding
Exit Ticket – 10 More 10 Less

5. Enrich/Reteach/Intervention
Adding Sets of 10 – start with 14 and use base ten blocks to add 10. Record and look at patterns. Modify to include 10 less. (located near bottom of web page under 1.NBT4)
Enrich
Go Math Chapter 7 E60 – students solve riddles using 10 less and 10 more