Watching your child grow can feel like a slow mystery — then suddenly their trousers are too short and they are raiding the fridge every afternoon. Growth between ages 5 and 12 is real but uneven, and most of what looks dramatic is completely normal.
How much do school-age kids grow each year?
From about age 5 until puberty begins, growth settles into a fairly steady pace. Most children gain roughly 5–7 cm (2–2.5 inches) in height and 2–3 kg (4–7 lb) in weight per year.
It rarely happens smoothly, though. Kids tend to grow in short bursts — a couple of weeks of fast change — with calmer stretches in between. So a few quiet months followed by a sudden jump in shoe size is the normal pattern, not a problem.
Every child has their own timing and build. What matters is that your child follows their own curve over time, rather than matching a friend or sibling exactly.
When do the growth spurts happen?
School-age children usually have two noticeable phases:
- Mid-childhood (around ages 6–8): a smaller, gentle pick-up in growth. Some kids also go through a brief “adiposity rebound” here, where they fill out a little before stretching up again — often normal.
- Pre-puberty (girls roughly 8–11, boys roughly 9–12): the big one. As puberty approaches, growth speeds up noticeably, and you may see rapid changes in height, foot size and appetite.
Girls often start this pre-puberty stretch a year or two before boys, which is why classmates the same age can look very different in height for a while. That gap usually evens out later.
Why is my child so hungry — and then not?
Appetite rides along with growth, so big swings are expected.
- Before and during a spurt, kids often seem permanently hungry and want larger or more frequent meals. That is their body fuelling new bone and muscle.
- In quieter stretches, the same child may pick at food and eat much less. This is not them “going off their food” — they simply need less right now.
The calm approach: offer regular, balanced meals and snacks, let your child decide how much to eat, and don’t turn it into a battle. If big appetite swings come with weight loss, tiredness or feeling unwell, that is worth a doctor’s visit.
What are growing pains?
“Growing pains” are a real and common thing, even though they are not fully understood and likely are not caused by the bones growing themselves.
Typical growing pains:
- Ache in the legs — thighs, shins, behind the knees — usually both legs.
- Show up in the late afternoon, evening or night, and are gone by morning.
- Leave no swelling, redness, limp or fever.
A warm bath, a gentle leg rub, a cuddle and reassurance are usually all that is needed. See a doctor if the pain is always in one spot, comes with a limp, swelling, redness, fever, or stops your child from walking or playing normally — those are not typical growing pains.
How do I track height and weight with percentiles?
Plotting your child’s measurements over time tells you far more than any single number.
- A percentile simply compares your child to others the same age and sex. The 50th percentile is “average”; the 10th or 90th are just as healthy — they are points on a normal range, not grades.
- What matters most is that your child stays roughly along their own curve. A child on the 25th line who keeps tracking the 25th line is growing well.
- Plot height and weight a couple of times a year, ideally at the same time of day, and look at the trend, not one reading.
Our child BMI calculator works out where your child sits for their age and sex, so you can follow the pattern over time instead of guessing from the number on the scale.
| Sign | Usually normal | Worth checking |
|---|---|---|
| Height gain | Steady along their own curve | Crossing several lines up or down |
| Appetite | Swings with growth bursts | Ongoing loss with weight drop |
| Leg aches | Both legs, evening, no limp | One spot, limp, swelling or fever |
When should I check with a doctor?
Most growth questions sort themselves out, but it is worth a chat with your doctor, school nurse or a paediatrician if:
- Your child crosses several percentile lines up or down over time.
- Growth stalls for a long stretch, or your child seems much shorter or taller than peers.
- There is weight loss, ongoing tiredness, or signs of being unwell.
- Puberty seems to be starting very early or very late for their age.
None of these mean something is automatically wrong — they are simply reasons to get a closer look from someone who knows your child. Trust your instinct: if something feels off, asking is always reasonable.
Related reading
This is general information, not medical advice — check with your doctor, school nurse or a paediatrician about your own child’s growth and health.
