Fluent adding and subtracting within 20
Fluently add and subtract within 20 using mental strategies; know from memory all sums of two one-digit numbers
Teaching approaches
Gakuva’s recommended starting approach is selected. You can still compare every option.
1 approach
Can your child instantly recall all the single-digit addition facts — like '7 + 8 = 15' — without needing to count or think for more than a second?
Fluently add and subtract within 20 using mental strategies; know from memory all sums of two one-digit numbers
Keep a record of your learning
Save photos, notes, and attendance. Export a proof packet for compliance or portfolio reviews.
Learning resources
Reviewed external links that reinforce this concept. They do not replace Gakuva’s teaching approach.
No reviewed resources for this concept yet.
The teaching approach above still stands. Curated practice links will appear here as the shelf fills.
Explore the learning path
2 before · 1 after
Before
This concept
Check understanding
- Answer any single-digit addition fact within 3 seconds
- Recall subtraction facts within 20 from memory (e.g. 15 − 8 = 7)
- Use known addition facts to derive related subtraction facts rapidly
“Can your child instantly recall all the single-digit addition facts — like '7 + 8 = 15' — without needing to count or think for more than a second?”
Curriculum record
- Type
- Procedural
- Subject
- Mathematics
- Domain
- Addition & Subtraction
- Age range
- Ages 7–8
Standards