T4T Number Talk  Dot Cards
Click to download full, formatted lesson and materials:
Lesson excerpt:
Number Talk: Dot Cards
In this lesson, students use dot cards as representations of numbers to build math language as well as fluency with decomposing numbers within 10.
NC Mathematics Standard:
Add and subtract within 20.
NC.1.OA.6 Add and subtract, within 20, using strategies such as:
• Counting on
• Making ten
• Decomposing a number leading to a ten
• Using the relationship between addition and subtraction
• Using a number line
• Creating equivalent but simpler or known sums
Standards for Mathematical Practice:
2. Reason abstractly and quantitatively
3. Construct viable arguments and critique the reasoning of others
7. Look for and make use of structure
8. Look for and express regularity in repeated reasoning
Student Outcomes:
● I can explain how I see groups that make up numbers within 10.
Math Language:
add
add to
put together
take from
take apart
minus
subtract
equal to
count on
compare
equation
make ten
doubles
Materials:
● index cards, dot stickers, chart paper
Advance Preparation:
● Prepare Dot Cards
o Create three cards that have similar patterns one with a total value of 8, then 9, then 10.
Example cards:
o Tape the first card to the chart paper on left side, leaving room to record what students say
Launch:
 Posing the Problem (1 minute)
· The teacher displays the first dot card and asks students: How many dots do you see? How do you see them?
Explore:
 Solving the Problem (12 minutes)
· Give students quiet think time to solve the problem mentally. Then they hold up their thumb to indicate when they have a solution and can share their strategy. Giving ample wait time is imperative.
Discuss:
 Sharing our Thinking (510 minutes)
 Ask students to share their answers. Teacher records all given answers.
For example, a student might explain I see 6 plus 2 more, so it equals 8.
You record 6 + 2 = 8.
 Ask the students to describe WHERE and HOW they saw it. Answers will vary.
 Ask who agrees. If someone disagrees, ask how they saw it. If all agree ask Did anyone see another way? The teacher decides how many volunteers should share. A suggestion at least three for each card. This can lead to rich discussion.
 Repeat this process (Launch, Explore, Discuss) with the next cards.
 As questions such as:
o How are these images alike?
o How are these images different?
o Do you see the same groups or different groups?
o How did you use your thinking from the previous card to determine the total?
o Is there a strategy that is more efficient with this arrangement of dots?
Evaluation of Student Understanding
Informal Evaluation: Observation
Next Steps Based on Informal Observations:
Whole Group 
Small Group Intervention 
Students are exploring addition within ten. The teacher may repeat this number talk using dot cards with different amounts and/or patterns. 
In small group use a Dot Card with between 2 and 6 dots.

Possible Misconceptions/Suggestions:
Possible Misconceptions 
Suggestions 
Students may just say facts they know once they hear the total rather than using the visual model.

Make sure students are asked HOW they see it. They can come up to show how if needed. Continue to use similar representations in subsequent number talks. As students become comfortable with mental math and talking about their strategies, they will become more flexible in their thinking. 
Possible Solutions:
Combinations that equal 8: 5+3, 4+4, 2+2+2+2, 3+3+2, etc.
Combinations that equal 9 and 10