1. Numbers 100 to 120 Unit of Study: Counting and Modeling Numbers to 120
Global Concept Guide: 4 of 4

2. Content Development
This fourth GCG will focus on the base ten representation of numbers
Students will not be exchanging 10 tens for a 100 flat. For example the number 114 will be represented as 11 tens and 4 ones.
The exchange of 10 tens for a 100 flat is the second grade standard for place value. By having students understand 116 as 11 tens and 6 ones in first grade is building the foundation for the structure of place value regrouping.
Students will record the standard form, base ten language, and quick pic.

3. Day 1
Essential Question: How can you model, read, and write numbers from ?
Engage/Building Conceptual Knowledge:
Pose the problem solving scenario to students: Amy has 100 stickers. Represent the stickers with base ten blocks or quick pics. (The teacher should be encouraging the use of quick pics and students should be relying less on the manipulatives.)
How can we record 100 stickers in tens and ones?
Emphasize the critical point that 10 tens equal 100. This follows the base ten system: 10 ones = 1 ten, 10 tens = 100.
Pose the following scenario: Amy got 8 more stickers and now she has a total of 108 stickers. Represent her stickers with base ten blocks or quick pics.
How can we record 108 stickers in tens and ones?
Compare the two representations- 100 and 108. What do you notice?
Have students predict the number of tens needed to model the number 105? Explain your prediction.
Students can write this prediction on a whiteboard, sticky note, or whisper to a partner. The goal is for students to understand the structure of the base ten system and be able to state 10 tens = 100.

4. Day 1 Continued…
Essential Question: How can you model, read, and write numbers from ?
Independent Practice: Go Math Lesson 6.9, On Your Own p. 275 #s7-11 (encourage students to draw the quick pic to match the base ten language), p. 275 #s & p. 276 #s
Monitor students as they are working on the independent practice. The teacher will not hear how the students are counting through 120 if they are not walking around, listening, and asking questions. If students seem to be miscounting, encourage student to use their pencil to mark the tens they have counted or use a pencil/tool as a pointer.
Closure: With the number 110, have the students draw the quick pic. This question can guide the lesson for day 2 since it is important for students to understand 11 tens and 0 ones.
By the end of Day 1, students should be able to model, read, and write numbers with numbers from 100 to 110.

5. Another example of how students should be recording these models.
Day 2
Another example of how students should be recording these models.
Essential Question: How can you model, read, and write numbers from ?
Engage: Go Math Lesson 6.10, Listen and Draw p Students will count a set of seashells by grouping ten groups of ten and some leftover ones. Use the guiding questions on p. 277 in the TE manual. Also, utilize the p. 277 Math Talk Question: How did you decide how many seashells there are?
Building Conceptual Knowledge: Pose the problem solving scenario to students: Amy has 120 stickers. Represent the stickers with base ten blocks or quick pics.
How can we record 120 stickers in tens and ones?
Have students predict the number of tens needed to model the number 117? Explain your prediction.
Students can write this prediction on a whiteboard, sticky note, or whisper to a partner. The goal is for students to understand the structure of the base ten system and be able to state 10 tens = 100.

6. Day 2 Continued…
Essential Question: How can you model, read, and write numbers from ?
Independent Practice: Go Math On Your Own p. 279 #s 5-13 and Problem Solving p. 280 #s
Closure: Discuss one of the problems from the independent practice- suggested p. 279 #11. Teachers can use the Math Talk in Action on p. 279 as a guideline to have a conversation about counting the tens and ones. The base ten model in #11 has the ones before the tens. Most models allow depict the tens then the ones and students have to have experiences with different representations of the same number.
By the end of Day 2, students should be able to draw a model, read, and write numbers from It is critical students are communicating 118 as 11 tens and 8 ones.

7. Day 3
Essential Question: How can you represent the numbers in more than one way?
Engage: Provide students with the number 112 and ask them to represent this number in two ways. For example, 11 tens and 2 ones or 10 tens and 12 ones.
Do these models have the same value?
Is there another way to represent this number?
Possible extension: The teacher can provide two base ten models that represent the same number (from ) and ask the students: What number does the model represent?; Do the models have the same value?; How are the models similar?; How are the models different?; Is there another way to represent this number?; What are all the ways to represent this number? (possible enrich question)
Building Conceptual Knowledge: Use the resource: Flexible Representations Students will flip a card, record the base ten language or model, and draw at least two more quick pics to represent the number. This task can be completed in a math journal/notebook.
For your reteach students, the teacher can complete this task in a small group.
By the end of day 3, students should be recording and drawing quick pics for multiple representations of the same number.

8. Enrich/Reteach/Intervention
Go Math Standards Practice Book p. P129 #6: Students will use a key with groups of tens and ones to determine the number of pens.
Go Math Enrich Book p. E54: Students will answer word problems where flowers are in groups on tens.
Core
Go Math Standards Practice Book p. p. 131 #s 1-7: Students will record a number from a base ten model and solve a word problem with rocks in groups of 10.
Reteach:
Go Math Reteach p. R54 and p. R55: Students will record the number from a base ten model. If needed, students can use the base ten manipulatives but since this is the end of the unit, highly encourage students to use quick pics.