Counting Back and Counting On(1)
Unit: Links Away
PreK to 2nd
Grace M. Burton
To set the stage for learning, choose a counting back book to read from the Counting Books Resource Sheet, such as Ten Sly Piranhas, Ten Little Ladybugs, or Five Little Monkeys Sitting in a Tree.
If no books are available, tell a story about counting back such as the following:
There were eight candies on
a plate. Zack took one of them; then Yula took one; then Xavier took
one, and Wilma took one, and so forth.
Next give each child 10‑12 links. Hold up a number and ask the
children to make a chain with that many links, lay it flat on the desk
and then record the number of links on their slates. Then ask them to
add one link and record the addition they have just modeled using the
equation (horizontal) format. Now show the same starting number and ask
the children to make a chain with that many links. Have students record
that number as before but this time to count away one link and then
record the subtraction they have just modeled using the horizontal
Now ask the students to build a chain of six links and hold the chain vertically so that it hangs down. Lead them in singing Six Little Ducks, from the Song Lyrics Resource Sheet, as they remove the links one at a time. Ask them to record each subtraction in vertical format.
When the children are ready, ask them to share one of their
differences and the counting process that was used to get it. Summarize
how students can count back to subtract one.
Questions for Students
1. How many links are in this chain (show a chain with ten links)? On this chain (show a chain with nine links)? Which chain has more? How many more?
[The chain with none links has more. It has one more link than the chain with ten links.]
2. What number sentence would show that you started with 10 links and took one away?
[10 – 1 = 9.]
3. What was alike between the two ways we recorded subtraction? What was different?
[The numbers we used were the same. We got the same answer. They look different because one is going across and one is going up and down.]
4. How could you help a younger child model this subtraction sentence (write 10 – 1)?
[Tell her to start with ten things and take one away.]
5. What does the minus sign mean?
[It means "take away."]
6. What two symbols did you use to mean equals?
[Two short lines and one long line. Students may point to the two symbols.]
7. When you count backwards, what comes after seven?
[Six comes after seven.]
Students will be able to:
Taking Away Sets
Grade: PreK to 2nd
Hopping Backward on the Number Line
Finding the Balance
Grade: PreK to 2nd, 6th to 8th
Finding Fact Families
Practice Makes Perfect
Looking Back and Moving Forward