Saturday revision sessions normally begin innocently. During a briefing, a smiling headteacher will announce that there is funding available for two or three Saturday revision sessions for some departments in the weeks leading up to the exams. NQTs and younger teachers usually jump at the chance as they get to show enthusiasm as well as receive a nice hourly wage to supplement their salary. It’s too good an offer to refuse. It’s only three Saturdays with only three hours on each day: what’s the big deal?

At this point, it actually isn’t a big deal. But wait...

The following term, or year, the headteacher makes a similar announcement. This time, Saturday sessions are available for an entire half term and for more departments than previously.

Also, you notice something else: the first time, the head was adamant that these sessions weren’t compulsory so there’s no feeling of obligation. This time, you are being served a cocktail. But, unlike the kind you long for on a beach during half term, this cocktail mixes: “Saturday sessions are not compulsory” with “we do what’s best for the kids”.  Soon enough, your line manager approaches you with nothing but a clipboard and a fake smile and asks which Saturday session you’re going to “volunteer” for.

You can see how this ends. Before you know it you are doing three Saturday sessions per half term with one important factor being ignored: you don’t want to. In fact, some callous academies use timetabling to bully staff who don’t partake: many teachers end up being issued a timetable with no exam groups and 20 different teaching rooms, simply for refusing to give up their own time.

So how do you avoid this?

Firstly, you must assume the pattern I’ve just described. Saturday sessions will multiply and if you’ve done some, it will be assumed that you will want to do more. Please note that you may be OK with doing more to begin with, but will you be OK with them being a normal part of your working life? It’s better not to do them in the first place and make your boundaries clear. (Do some tuition if you want the extra cash; there are far fewer repercussions.)

Secondly, if you decide to refuse, have your excuse ready: “I can’t, I have a wedding to go to.” Make sure your excuse is something solid that cannot be rearranged, for example, you’ve booked a weekend away or it’s your nephew’s christening. If you’re later asked about the event, just recall an actual event of the same nature. If your moral code forbids you from lying, take comfort in the fact that you are acting out of necessity, and it’s actually nobody’s business how you spend your weekends.

Thirdly, camaraderie is key. If you are at an academy which does everything described and you fear what might happen to you if you refuse to do Saturday intervention, while your first option should be to diplomatically refuse, another is to share the burden. Stick together and make sure everyone takes a slight hit, for example, one Saturday each for a term.

The average teacher works 55 hours a week - even more for an NQT. A well-respected colleague and friend of mine once said: “Money can be made again. But when the time is gone, it’s gone forever.”

Spend Saturdays doing things that excite you. You spend the majority of your waking hours working during the week.

Don’t work on a Saturday. Your happiness is ultimately what’s best for the kids.

Omar Akbar is a science teacher and author of The (Un)official Teacher’s Manual: What they don’t teach you in training