Counting objects to 20
Count up to 20 objects in structured arrangements, count up to 10 scattered objects, and count out a requested amount from 1 to 20.
What a learner can do afterwards
- Accurately count up to 20 objects in a line
- Count up to 10 scattered objects without losing track
- Given a number 1–20, count out that many objects from a larger set
1 · Read
Start at 1. Touch each object once and say the next number. The last number tells how many objects there are. After 10, say 11, 12, 13, 14, 15, 16, 17, 18, 19, 20. Moving objects into a new arrangement does not change their total.
To count objects in groups, keep your count going. These apples are in two groups of 6. Count the first group from 1 to 6. Continue through the next group: 7, 8, 9, 10, 11, 12. There are 12 apples altogether.
To count out a requested amount, move one object at a time into a new pile. Say one number for each object you move. For 9 blocks, stop after saying 9. The new pile then holds the requested amount.
You need 14 counters and have counted out 11. Continue with one new counter for each number: 12, 13, 14. You moved 3 more counters. Stop when you reach the target. Count the new numbers to find how many more objects you need.
If you lose track, start again at 1. Touch each object once. With real scattered objects, you can move each counted object aside. This helps you keep track. A careful recount is a useful check, but matching answers do not prove that both counts were correct.
Skipping an object leaves it without a number. Your count then comes out too small. Counting an object twice makes the count too big. If you touch every object once but repeat a number name, check the number sequence too.
Count every object once, all the way up to 20, no matter how they are arranged.
The readings, questions and flashcards were written for this dataset. The linked videos are by Khan Academy.
2 · Watch
Take it off screen
Where it sits
18 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.