Primary 4 covers numbers to 100 000: place value to ten thousands, reading and writing numbers, comparing and ordering, number patterns, rounding to the nearest 10, 100 or 1000, and the ≈ symbol.
What numbers up to 100 000 actually asks of a Primary 4 student
Rounding is the new idea, and it is the first time mathematics asks a child to give an answer that is deliberately not exact. That is a genuine conceptual shift after four years of being told to be precise.
It is also the foundation of estimation, which the syllabus returns to repeatedly. A student who can round confidently can check every later answer for reasonableness in a couple of seconds.
The ≈ symbol appears here too, and using it correctly rather than writing = is part of what is marked.
What the syllabus covers
Under the MOE primary mathematics syllabus, numbers up to 100 000 at Primary 4 covers:
- number notation, representations and place values (ten thousands, thousands, hundreds, tens, ones)
- reading and writing numbers in numerals and in words
- comparing and ordering numbers
- patterns in number sequences
- rounding numbers to the nearest 10, 100 or 1000
- use of ≈
Where the marks actually go
Rounding to the wrong place. Asked for the nearest hundred, the child looks at the hundreds digit rather than the tens digit that decides the rounding.
Numbers exactly halfway are rounded down. The convention is to round up at 5, and it needs stating rather than assuming.
Using = where ≈ is required, which loses the mark even though the number is right.
How to practise this properly
Teach rounding as “which of the two neighbours is it closer to?” rather than as a digit rule. A child who can name both neighbours will get it right without memorising anything.
Underline the deciding digit before rounding. Making it a physical step stops the child looking at the wrong column.
Use a number line for the halfway cases until the convention is automatic.
Round the same number to 10, 100 and 1000 in one exercise. Seeing the three answers side by side makes clear that rounding depends entirely on what you were asked for.
What this leads to
Estimation runs through Primary 5 and 6 and into secondary school, and rounding to a specified degree of accuracy reappears in the decimals topic later this same year.
Almost every primary topic is scaffolding for a later one, and the scaffolding is invisible until it gives way. That is why our curriculum is written across all six years, Primary 1 to Primary 6, rather than level by level — it lets us see the whole structure a child is standing on, not just the step they are currently on.
What lessons at Odyssey are actually like
Our students describe the teaching in their own words. This one is a secondary student — the approach is the same one your child would meet in a primary class, taught at the right level. More are on Odyssey Math TV.
Getting help with this topic
We teach Primary 4 maths in small classes at Hexacube, 160 Changi Road #01-02, about three minutes from Eunos MRT. You can see our class schedules and fees, read about our math tutors, or look through the primary school math tuition programme as a whole. If your child is in a nearby school, our primary school directory may be useful too.
If you are unsure whether tuition is the right answer yet, the free trial is a reasonable way to find out without committing to anything. We will give you an honest read on where your child stands and what would actually help. Book a free trial class or WhatsApp +65 8512 6882.
What we describe here comes from teaching this syllabus in our own classes since 2012. It is not a forecast for any individual child: progress is produced jointly, by a student willing to do the work with support at home. We do not promise grades. Topics follow the MOE primary mathematics syllabus — check the current syllabus on the MOE website for the definitive version, and see our curriculum page for how we teach it.
Frequently asked questions
How large are numbers at Primary 4?
Up to 100 000, with place value extending to ten thousands.
Which digit decides the rounding?
The one immediately to the right of the place you are rounding to. For the nearest hundred, look at the tens digit.
What happens at exactly halfway?
Round up. A number ending in 50 rounds up to the next hundred.
When should ≈ be used instead of =?
Whenever the value has been rounded, because the two quantities are no longer exactly equal. Questions do mark this.
