Students will be able to compose groups of 10 to count within 100.
Students will be able to describe the value of digits in the tens and ones places using manipulatives and partner support.
Tell the students the story problem, "Sara is in Room 12, and Samantha is in Room 21. Sara's little sister thinks that they are in the same classroom, because both room numbers have a two and and a one in them. Do you agree with Sara's sister? Why or why not?"
Instruct students to sit knee to knee with a partner and explain their thinking using the sentence frame, "I agree/disagree with Sara's sister because ________."
Choose a few students to share. Possible responses include that 21 is more than 12, 21 is farther than 12 on the number line, 12 has one ten and two ones, and 21 has two tens and one one.