Quickly recall subtraction facts within 20.
Where your child meets this in real life: Making change, calculating differences, or solving problems quickly
SEAGReady breaks subtraction facts within 20 into 3 steps, taught in order so each skill builds on the last.
Recall subtraction facts where both numbers are 10 or less (e.g., 9 - 4 = 5)
Subtract from numbers 11-20 where the result stays in the teens (e.g., 17 - 4 = 13)
Subtract from numbers 11-20 where the result crosses back through 10 (e.g., 15 - 8 = 7)
Three free sample questions from our subtraction facts within 20 course. Every question comes with a full explanation, and hints that guide without giving the answer away.
Sean has 8 apples. He gives 3 to his friend Aoife. How many apples does Sean have left?
Answer: A. 5 apples
Sean starts with 8 apples and gives away 3. Think: what adds to 3 to make 8? 3 + 5 = 8, so 8 - 3 = 5 Sean has 5 apples left.
Stuck? Start here: Sean is giving away apples, so he will have fewer. What operation do you need?
Conor has 16 football stickers. He trades 3 of them with his friend. How many stickers does Conor have now?
Answer: B. 13 stickers
Conor has 16 stickers and trades 3. 16 = 10 + 6 Subtract from the ones: 6 - 3 = 3 The ten stays the same: 10 + 3 = 13 Conor has 13 stickers.
Stuck? Start here: Conor is trading away stickers, so he'll have fewer. What's the calculation?
Ciara baked 14 biscuits for a school fair. Her family ate 7 before she could take them. How many biscuits does Ciara have left for the fair?
Answer: C. 7 biscuits
Ciara has 14 biscuits and 7 are eaten. Bridge through 10: 14 - 4 = 10 (that's 4 of the 7) 7 - 4 = 3 more to subtract 10 - 3 = 7 Ciara has 7 biscuits left.
Stuck? Start here: Biscuits were eaten, so Ciara has fewer. What's 14 - 7?
This is the exact interactive worked example your child sees in SEAGReady. Step through it and watch the method build up.
Ciara has 9 sweets. She gives 4 to her brother Oisin.
How many sweets does Ciara have left?
9 − 4
Step 1 of 3
Ciara has 9 sweets. She gives 4 to her brother Oisin.
How many sweets does Ciara have left?
Ciara has 5 sweets left.
The key insight: Subtraction and addition are opposites! If you know 4 + 5 = 9, you also know 9 − 4 = 5.
Watch out: Counting back on fingers and losing track. Using addition facts is faster and more reliable than counting backwards.
These are the misconceptions we see most often in subtraction facts within 20, including the ones our practice questions are specifically designed to catch.
Struggling with subtraction facts within 20? The real gap is often in one of these earlier topics.
SEAGReady finds the exact step where your child gets stuck, teaches it with worked examples like the one above, and brings it back for review so it sticks.