Counting On to Determine How Many Dots
- Engage students in "Counting On"
- Supporting conceptual understanding
What to Look for in This Clip:
"Counting on" is a strategy that students use to help solve addition problems. As students get more comfortable with addition problems, they move from "counting all" of the objects in two sets starting with the number one, to "counting on" from the total number of objects in the first set to determine the total.
In this scenario, the teacher guides a student to use this strategy as he works to figure out how many dots are on each domino. The teacher does a nice job of supporting the student's conceptual understanding of the strategy by scaffolding it in a step-by-step way.
At first, she reveals only one side of the domino and asks the student to identify how many (two). Then, she shifts her finger to reveal the other side and prompts him to count the six dots. As she reveals the first two dots again, she prompts the student to "count on" by saying, "Say six. Now, keep counting: seven, eight, eight." She stresses that the last number they said, "eight," is how many dots there are altogether.
When the students picks another domino with the combination of 3-dots and 6-dots, the teacher scaffolds the student to use the "counting on" strategy again, and the student is able to use it to reach the correct answer (nine).