One engine. Every school shape.

Every DP student builds their own diploma: one subject from each of six groups, three or four of them at Higher Level and the rest at Standard, plus Theory of Knowledge, the Extended Essay and CAS. Two students in the same year group can share almost no lessons.

Schedual models that literally. There is no notional “class 12A” that everything hangs off — each student carries their own subject-and-level combination, and HL and SL are separate teaching groups with different weekly hour requirements, because an HL course is not an SL course with extra time bolted on.

DP1 and DP2 can be taught together where a subject is too small to run twice, and Schedual will combine them into one group only where the curriculum and the room both allow it.

CP students take at least two Diploma courses alongside a career-related study and the CP core — personal and professional skills, service learning, a reflective project and language development.

The DP courses are solved in exactly the same pool as the Diploma students’, so a CP student sits in the real DP class rather than a duplicate of it. The career study, which often runs off-site or in long blocks, is placed around that academic spine.

MYP runs eight subject groups for every student across five years, so the choice model is the opposite of the Diploma: almost nothing is optional, and the difficulty moves from individual choice to sheer volume and to interdisciplinary requirements.

Cohorts are timetabled as whole blocks, with design, arts and physical education rotating through shared specialist spaces. In MYP 4 and 5, where schools begin to offer restricted choice, those become option blocks handled the same way as GCSE options.

The personal project in MYP 5 and the interdisciplinary units are given protected time rather than being squeezed into what is left over.

A PYP class stays with its homeroom teacher for most of the week and is released to specialists — languages, music, PE, library, the arts — at fixed points. The constraint that actually bites is that releases must be balanced: a homeroom teacher needs their planning time, and the specialist cannot be in two classes at once.

Units of inquiry are protected as long blocks rather than fragmented, and the exhibition year is given its own dedicated time.

IGCSE students take a compulsory core — usually English, mathematics and at least one science — and then choose the rest from option blocks. Many subjects are additionally split into Core and Extended tiers, which are separate teaching groups with separate room and teacher requirements even though they share a subject name.

Schedual builds the option blocks from the choices your students actually made, rather than asking you to guess the blocks first and then discover that thirty-one students picked an impossible combination.

At GCSE, students carry a compulsory core and pick three or four options; the blocking problem is to arrange those picks so that every basket in the year group resolves. At A-Level the numbers are smaller but the combinations are wilder — three or four subjects chosen freely, with Years 12 and 13 often taught together in the less populated ones.

Where a set of choices genuinely cannot be blocked, Schedual says so and names the conflicting combinations, instead of silently dropping a student from a subject they chose.

The French system has its own shape and does not survive being flattened onto an English one. Seconde is almost entirely tronc commun, taught in form classes. In Première each student adds three spécialités; in Terminale they drop one and keep two at a heavier weekly load, alongside options such as maths complémentaires, LCA or a third language.

Schedual keeps the classe as a real object — students stay with their form group for the tronc commun and split out only for spécialités and options, which is how a lycée actually runs. Spécialité blocks are pinned and spread across the week so a student never takes all of one subject in a single day.

At full lycée scale — seven hundred students and up — this needed a dedicated solving path rather than the generic one, and it has one.

A US high school timetable is a credit problem as much as a scheduling one: students work toward graduation requirements over four years, choosing electives each year, with Honors and AP sections of the same course running alongside the regular one.

Schedual handles the common structural variants — a straight period day, a block or A/B rotation, and advisory or homeroom periods — and treats AP and Honors as distinct sections with their own teacher qualification requirements.