Lesson 5

The 100 Chart

Est. Class Sessions: 1–2

Summarizing the Lesson

Mystery Number Riddles on the 100 Chart. This part of the lesson give students more opportunity to explore number relationships such as between, closer to, more than, and less than. To develop these concepts, tell students you want them to solve a number mystery using the clues that you give them. Display the 100 Chart page in the Student Activity Book Reference section and use problems such as the one in the example. Encourage students to explain their reasoning when discussing solutions.

Slide your fingers on the numbers 30 through 40 on the 100 Chart display and begin by saying:

X
  • I'm thinking of a number that is between 30 and 40.
  • The number is closer to 40 than to 30. Which numbers on the chart could it be? (36, 37, 38, 39, 40)
  • The number is two more than 35. What is the mystery number? Explain how you know. (37; Possible response: I know that if I count on 2 from 35, I get 37.)

See Figure 3 for more riddles to share. Encourage them to use what they learned during the lesson to solve the riddles and to clearly explain their thinking. Note growth in students' reasoning and communication about these ideas. Ask students to make up their own riddle and ask a partner to solve it.

Adventure Book:
Student Activity Book:
X
SG_Mini
+
Master:
Additional mystery number riddles and responses
X
+