1st Grade Counting and Numbers to 20 Worksheet Solutions (PDF)
This numbers to 20 answers for 1st Grade covers counting and numbers to 20 (Common Core 1.NBT.A.1), with a free PDF to print.
Here are the full answers for all 20 problems. Each one shows how to count, with ten frames and number lines to check the work. Read the steps with your child and count together.
Grade 1 · Common Core State Standards: 1.NBT.A.1
Numbers to 20 answers: exercises 1 to 10
Exercise 1 – Count the stars
Touch each star once and count: 1, 2, 3, 4, 5, 6, 7.
\(7\)
Exercise 2 – Count the ten frames
The first frame is full: 10. The second frame has 2 counters. Ten and two more is 12.
\(12\)
Exercise 3 – Numeral for a word
Nine is written \(9\).
\(9\)
Exercise 4 – Teen word to numeral
Sixteen is ten and six more, so the numeral is \(16\).
\(16\)
Exercise 5 – Next number
After 10 we say 11.
\(11\)
Exercise 6 – Missing number in a row
The number between 5 and 7 is 6.
\(6\)
Exercise 7 – Hop right
One step right of 16 is the next number, 17.
\(17\)
Exercise 8 – Hop left
One step left of 12 is the number before it, 11.
\(11\)
Exercise 9 – Number line gap
The ticks go 13, 14, then the box, then 16. So the box is 15.
\(15\)
Exercise 10 – Count back
Count back: 12, 11, 10, 9.
\(10\)
Exercises 11 and up
Exercise 11 – Fill the frame
The frame has 6 counters and holds 10. Count the empty boxes: 7, 8, 9, 10. That is 4 more.
\(4\) more
Exercise 12 – Ten and some more
Ten and three more is 13.
\(13\)
Exercise 13 – Count on three
Say 15, 16, 17.
\(15, 16, 17\)
Exercise 14 – Missing end of the row
The row goes 15, 16, 17, 18, 19, 20.
\(17\) and \(20\)
Exercise 15 – Sticker book
One more than 17 is 18.
\(18\) stickers
Exercise 16 – Apple basket
One less than 11 is 10.
\(10\) apples
Exercise 17 – Block towers
Ten blocks and five more blocks is 15 blocks.
\(15\) blocks
Exercise 18 – Shell collection
Monday: 9. Tuesday, one more: 10. Wednesday, one more: 11.
\(11\) shells
Exercise 19 – Counting to twenty
She says 17, 18, 19, 20. That is four numbers.
\(17, 18, 19, 20\)
Exercise 20 – Mystery number
Count back one step from 20. You say 19.
\(19\)
Key facts behind this numbers to 20 answers
- Touch each object once and say one number for each touch.
- The last number you say tells how many objects there are.
- A full ten frame holds 10 counters; a second frame shows 11 to 20.
- One more is the next number; one less is the number before.
- A numeral such as 14 is the written symbol for fourteen.
How to use this numbers to 20 answers
Cover each solution, solve the exercise again, then uncover it and compare every line. If your answer differs, find the first step that changed and redo the exercise from there.
All Grade 1 chapters: Grade 1 math.
