The seven steps
- Gather the grade in one list. One row per student: name, this year's class, and only the details you will balance on, such as gender, reading and math bands 1 to 4, and behaviour, English learner and support flags.
- Agree what balanced means before you start. Decide as a team which measures matter and which matter most, so the lists are judged against the same yardstick.
- Collect friend requests and separations. Up to three ranked friends per student, pairs who must be kept apart, and siblings or twins to keep together or apart.
- Set the classes, teachers and caps. How many classes, who teaches each, the most students each can take, and any combined class and the grades it takes.
- Build a first draft. Place every student without breaking a separation or a cap, keeping each class close to the grade's own mix and giving each child a friend.
- Check every class against the whole grade. Compare the counts per class side by side and read every request that could not be met, with its reason.
- Review with the people who know the children. Teachers, specialists and the principal adjust by hand, lock what is settled, rebalance the rest, and sign off.
School placement policies read the same way from district to district. One lists academic skills, work habits and behaviour, relationships, gender, cultural diversity and class size; another lists the range of academic ability, the numbers of boys and girls, behaviour, special education needs and how personalities interact. A 2026 teacher guide adds learning plans, English learners and friendships. A study of three elementary schools found that schools collecting much the same data still decided very differently, which is why agreeing the measures first (step 2) matters. The sources below were read on the date shown.
Worked example: 60 students into 3 classes
The sample grade in the class builder is 60 invented Year 3 students in three classes, moving up to three Year 4 classes with a cap of 21. The grade has 30 girls and 28 boys, 8 English learners, 6 students with the behaviour flag and 7 with the support tag. 54 students named friends, and there are 8 keep-apart pairs and one pair of twins to keep together.
First, the shortcut many teams are tempted by: move each class up whole. Every friend request is met, because most friends are in the same class now, but 4 keep-apart pairs end up together and the balance drifts:
| Class | Students | Girls, boys | Average reading band | Behaviour | English learners | Support | Friend met |
|---|---|---|---|---|---|---|---|
| 4A | 20 | 8, 12 | 2.6 | 3 | 4 | 2 | 19 of 19 |
| 4B | 20 | 13, 6 | 2.7 | 3 | 3 | 2 | 17 of 17 |
| 4C | 20 | 9, 10 | 2.5 | 0 | 1 | 3 | 18 of 18 |
Then the lists the builder makes from the same grade, with every keep-apart pair apart and the twins together:
| Class | Students | Girls, boys | Average reading band | Behaviour | English learners | Support | Friend met |
|---|---|---|---|---|---|---|---|
| 4A | 20 | 10, 9 | 2.6 | 2 | 3 | 3 | 19 of 19 |
| 4B | 20 | 10, 9 | 2.7 | 2 | 3 | 2 | 16 of 16 |
| 4C | 20 | 10, 10 | 2.5 | 2 | 2 | 2 | 19 of 19 |
Every class now sits within one student of the grade's mix of girls and boys, the behaviour flags are spread two, two and two, and 54 of 54 students have a friend they asked for (33 have their first choice). The builder's imbalance score falls from 1705 to 93. The same grade, rules and seed give the same lists every time, so a colleague can rebuild them and check.
Common mistakes
- Balancing on everything. Every extra measure pulls against the others. Pick the few that matter to your school and switch the rest off.
- Promising friend requests. A request is a preference. Say so to families, and keep the reason for any request not met.
- Checking classes one at a time. A class can look fine alone and still hold most of the grade's behaviour flags. Compare every class side by side.
- Forgetting the new students. Leave a seat or two below each cap for enrolments over the break.
- Letting the tool decide. A balancing tool only balances what it is told. The teachers who know the children should review every list before it is shared.