How to build a school timetable: a step-by-step guide

Building a school timetable is one of the biggest pieces of planning a school does all year. It touches every student, every teacher and every room, and it has to be right before the first day of term.

The good news is that it follows the same sequence every year. Get the early steps right and the later ones get much easier. This guide walks through that sequence for a typical UK secondary school.

1. Start with the curriculum plan

The timetable delivers the curriculum, so it starts there. For each year group, write down:

• Every subject and how many periods a week it gets. For example, Year 9 maths gets four periods a fortnight more than Year 7.
• How students are grouped. Mixed-ability tutor groups, sets, or bands. Which subjects are set, and against which others?
• What runs in parallel. If maths is set across the whole year group, every maths group has to be taught at the same time.
• Options in the upper years. Which subjects students choose between, and how the choices will be collected.

Agree this with senior leaders and heads of department before anything is scheduled. Most painful timetable rework comes from someone discovering in July that the plan they agreed isn't the plan that was built.

2. Turn it into a staffing plan

Next, check that you have the people to teach the curriculum. For each subject, add up the periods the curriculum needs and compare them with the periods your teachers can teach, allowing for part-time contracts, leadership time and planning time.

If a subject needs more periods than you have teachers for, you'll find out now rather than halfway through scheduling. We cover this step in more depth in from curriculum plan to staffing plan.

3. Collect every constraint

Now gather the rules the timetable must follow. Separate them into two lists:

• Hard constraints can never be broken: no teacher or room double-booked, no student in two places at once, part-time staff only on the days they work, labs for practical science.
• Soft constraints are preferences: fewer gaps in students' days, no double PE last thing on a Friday, staggered lunch.

Be strict about which is which. Every preference you promote to a hard rule makes the timetable harder to build, and can make it impossible. Our guide to hard and soft constraints explains how to sort them.

4. Fix the structure of the week

Decide the shape of the school day and week:

• One-week or two-week timetable
• Number and length of periods
• Break and lunch times, and whether lunch is split
• Where registration and assemblies fall

Changing the structure later means starting again, so settle it early.

5. Build the option blocks (if you use them)

If upper-year students choose subjects through option blocks, design the blocks from students' choices before you schedule anything else. Each block becomes a slot in the timetable where all its subjects run at once. See our guide to option blocks for how to do it.

6. Schedule the hardest pieces first

Whether you build by hand or with software, place the most constrained pieces first:

1. Whole-year-group setting, like maths and English sets, which need many teachers at once
2. Option blocks
3. Part-time teachers and anyone with restricted availability
4. Specialist rooms that are in short supply, like labs, sports halls and music rooms
5. Everything else

Leaving a hard piece until the end is how timetables reach 95% complete and then stall.

7. Check the timetable against your goals

A timetable with no clashes isn't automatically a good one. Before you sign it off, check:

• Student experience. How many free periods are stranded mid-day? Are any subjects bunched at the start or end of the week? (More on reducing student free periods.)
• Teacher workload. Is any teacher teaching every period on one day and nothing the next?
• Rooms. Are labs and specialist rooms used for the lessons that need them?

8. Publish, then plan for change

Publish timetables to students, staff and your MIS. Then accept that things will change: staff leave, numbers shift, a new class is needed in October. Keep the original data and settings so you can make changes without starting from scratch, as covered in changing a timetable mid-year.

Where software helps

Steps 1 to 5 are decisions only your school can make. Steps 6 and 7 are where most of the hours go, and they're what timetabling software is for.

Timez takes your students, staff, rooms, subjects and availability and handles step 6 automatically. It meets every hard constraint and works to cut student gaps, teacher gaps and lunch congestion. Then it reports the numbers you need for step 7, so you can check the result, adjust a setting and run it again.