A number bond is a small diagram: the whole number sits in a circle at the top, and the parts it is made of sit in circles underneath, joined by lines. It shows that a number can be taken apart and put back together. Children use it to make ten while adding, and it is the same whole-and-parts idea they meet again in algebra when they solve x + 7 = 12.
Read the guide Commonly taught in Eureka Math and EngageNY and in most US elementary programs, grades 1–4.
Make ten and compensation are ways of rewriting a problem so the adding happens in your head. You shift a small amount from one number to the other to land on a friendly number — 10, 100, or a whole ten. The total does not change, and being able to say why is the part the page is testing.
Read the guide Commonly taught in Eureka Math, EngageNY and Illustrative Mathematics, grades 4–5.
That rectangle is the area model. It splits a multiplication into four smaller multiplications you can do in your head, then adds them. It is the same arithmetic you learned — it just shows where each part of the answer comes from.
Read the guide Commonly taught in Eureka Math, EngageNY and Illustrative Mathematics, grades 4–6.
That column of subtractions down the side of the page is partial quotients. Instead of finding one digit of the answer at a time, your child subtracts a large, easy multiple of the divisor, writes down the multiple used, and repeats until nothing is left. The multiples written on the side are added at the end to get the quotient. It is the same answer you would get from long division.
Read the guide Comes from Singapore Math — the Primary Mathematics series and Math in Focus — and is used widely in US schools, grades 2–6.
A bar model is a rectangle drawn to hold the numbers in a word problem and show how they relate. One bar can stand for a whole that is split into its parts, or two bars can be placed one above the other to compare two amounts. The drawing turns the sentence into something the child can do arithmetic on.
Read the guide Commonly taught in Eureka Math and EngageNY, grades 6–7. The same strip of equal parts appears in fraction and percent problems in grades 4–6.
That strip of boxes is a tape diagram. Each box is one equal part, and the ratio tells you how many boxes to draw. You find what one box is worth, then multiply. It is a picture of the sharing, not a different kind of arithmetic.
When the working is shown, the child can see exactly which step to change. That is the same idea as our lessons: an attempted answer, a principle, then one next step.
You do not have to be the teacher
You need one good question — “what is this part measuring?” — not a working knowledge of the current curriculum. Every guide below ends with what you can usefully say.
These guides describe methods as they are commonly taught; your child’s teacher or school may use different names for the same steps. Treat them as a starting point for a conversation, not a replacement for your teacher’s guidance.