Worksheet guide
What is on the number bonds sheet
Each question shows a part-whole bar: the whole on top and two parts below, with one part blank. The matching equation sits above the bar, so a child sees 7 + _ = 12 and the same relationship drawn underneath.
The whole is set by the year and difficulty. Year 1 works to 10, Year 2 to 20, Year 3 to 100 with multiples of ten, and the upper years move to 100 and 1,000. The bar is drawn to scale, so a missing part that is nearly the whole looks nearly the whole.
Why bonds matter
Number bonds are the mental arithmetic that everything else rests on. A child who knows that 8 and 2 make 10 can add 8 + 5 by making ten first, subtract 9 by subtracting 10 and adding 1, and later partition numbers for column methods without being told to.
They also make the inverse relationship visible. The same bar shows 7 + 3 = 10, 3 + 7 = 10, 10 − 7 = 3 and 10 − 3 = 7. Four facts, one picture, and no need to teach subtraction as a separate topic.
Using the sheet at home
Five minutes a day is plenty. Start with bonds to 10 until they are instant, then move to 20, and only then to 100. Printing a sheet that hides the part, the other part and the total is a good check: a child who can do 7 + _ = 12 but not _ + 5 = 12 has learned a position rather than a relationship.
The answer page makes it possible for an adult to check without doing the arithmetic, which matters when the adult is not confident with maths themselves.
Bonds beyond the sheet
Bonds are worth practising away from paper too: pairs of socks, stairs, cutlery, anything that can be split into two groups and put back together. Ten seconds of that on the way out of the door does more for recall than a second sheet, and the printed page is there when you want a record of what has been practised.
How to use it
How to use this generator
- Choose Number bonds; the part-whole bar is drawn automatically.
- Use the Year dropdown to set the whole: 10, 20, 100 or 1,000.
- Print 20 questions at 18 pt for younger children.
- Mark from page 2, or print page 1 only.
FAQ
Frequently asked questions
What are number bonds?
Pairs of numbers that add up to a given total. Bonds to 10 are 0 + 10, 1 + 9, 2 + 8 and so on; bonds to 20 are the pairs that make 20.
Which bonds should children learn first?
Bonds to 10, because they underpin the make-ten strategy for addition and the bridging strategy for subtraction. Bonds to 20 and 100 come after.
What is a part-whole model?
A diagram with the whole at the top and the two parts below, joined by lines. It shows that a whole can be split into parts and that the parts can be recombined.
Are number bonds the same as fact families?
Related but not identical. A fact family is the set of four equations a bond produces: 7 + 3, 3 + 7, 10 − 7 and 10 − 3. The bond is the underlying relationship.
Can I print bonds to 100?
Yes. Choose Year 3, which sets the whole to 100 and uses multiples of ten so the arithmetic stays mental.
Does the answer page show the bar?
Yes. The answer page repeats the same layout with the missing number filled in red, so the picture and the answer match.
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