So you've gone in hard, your face is stiff from the effort of not smiling and your seating plan looks like a war-room map. By some miracle, the students have responded. They're listening, they're producing good work and they look like they might actually be proud of what they're doing. Congratulations, you've just unlocked one of the hardest achievements in teaching: that of "master of the classroom". It's a prestigious position and one that should be savoured.
But what happens once you have got them where you want them to be? Do you have to continue to play bad cop until they're saying goodbye at the prom? Or do you let it all hang out and risk relapse and mutiny?
It's a Herculean effort to gain control of 30-odd young people, so the desire to stick to proven tactics is completely understandable. After all, consistency is a key facet of behaviour management. But keeping up that kind of guard for a whole academic year (and beyond) is incredibly difficult and, if anything, almost as stressful as ducking flying chairs. To put it another way: it's hard being hard all the time.
There is an alternative. It requires a subtle balancing act and some courage, especially if you're fairly new to the game, but I find it works very well. It amounts to a simple statement: this is your class and, as a teacher, you don't have to stick to the rules. The students do, you don't.
I know! So unfair, right? Especially after all that talk of consistency and such like. But as the source of authority in the classroom, you're allowed to decide whether Aiden and Liam digging each other in the arm just before they sit down warrants the same level of sanction it would have earned them at the start of the year.
You might decide that a small pause and a withering look instead of a recorded warning is enough in some cases. Alternatively, a good-natured put-down - yes, students do have a sense of humour - could be sufficient to stop unwanted behaviour that would formerly have meant a black mark on a weekly report and possible escalation. A minor indiscretion does not have to be jumped on with both feet until there's nothing left but a gooey puddle.
Building up a trust fund
Good relationships with the class go some way towards making this tactic work. If you've spent time gaining the trust of the students by keeping classroom discipline to a standard where everyone can get on, the chances are that they will trust you when you decide a situation dictates a deviation from the formula. If you've put in the groundwork, you can afford to not bring down the full force of the law. The other students will know you're not going to let them get away with daftness if it continues.
This requires you to remain fair and stern when appropriate. There will always be times when sticking rigidly to the behaviour policy you started with is desirable and necessary, but smooth lesson flow has to be a consideration when dealing with the minor stuff. It's no longer a grudge match; it's a dance.
So how do you pick the indiscretions to overlook, the ones to greet with mild rebuke and the ones to throw the book at? It is tough and unfortunately there is no simple answer. It comes down to trial and error. Every class is different and you will need to shift your behaviour to match theirs.
The good news is that making these judgements does get easier as you gain more experience and get to know your classes better. For some groups, you might decide that it's worth the effort of sticking to the rules all the way down the line, because they are liable to become all kinds of awful if you loosen the reins even a little. And that is understandable.
However, even in these situations, it is sometimes worth giving an inch. It helps to develop relationships, allows for flow in your lesson and - probably most importantly - takes a little pressure off you as well. Try it, and if they start taking the mick, you can always put your best stomping boots back on.
Tom Starkey is an English teacher at an FE college in the north-east of England. He blogs at stackofmarking.wordpress.com and is on Twitter @tstarkey1212