Monday, February 12 9am: A part-time teacher has fallen down the stairs at home and has 20 stitches in her head. A full day’s worth of cover needed. Notice from the timetable that she is down for weekly cover during her 40-minute lunch break. Not surprised she fell. Probably from exhaustion.

10.45am: Break duty with member of department. He tells me he has a black lump between his scrotum and anus. He fears the Big C. I suggest in-growing hair.

11.40am: After teaching the most distressed Year 8 class I can remember, I find an intelligent, sensitive Year 11 student in the deputy head’s room being counselled. I am called in to throw in my “pearls”. The pupil is sobbing, hopeless and utterly helpless. Has spent weekend “holding the razor” and plans to kill. Shows us numerous cuts on both arms.

12.15pm: Sweep pupil into lunch. Can’t die on an empty stomach.

2pm: Cover one of the lessons of the “stitched- up” absent teacher. Lower ability Year 9, 31 pupils, more boys than girls. The group is wild, whooping around the room. They are clearly disillusioned with the usual teacher, who has missed more than half of their lessons. Children I tamed and entertained last year have lost it. Insist everyone sits in alphabetical order but the behaviour and group dynamics is far from my teaching and learning expectations.

Tuesday, February 13 9am: In-growing hair colleague is at doctor. Other member of department accompanies wife to casualty.

2.45pm: Lesson nine, 35 minutes with yesterday’s wild Year 8 group. Nothing done. There’s fighting in the corridor and I cannot make myself heard. Usher the children downstairs to shame them into submission in the eye of the general office, head and visitors. The head is not available. He is with the pay threshold assessor.

I harangue the group. Their head of year pops his head out of the hall and takes the worst offender. Order is established. The group returns to class with 10 minutes’ teaching and learning time left. This has been going on every Tuesday since September.

4pm: Police car on site. Hoodlum who was expelled for attacking teacher with screwdriver 11 months ago has kicked a supply teacher in the chest as the latter left the premises. Spend the evening writing notes for the chair of governors about a parental complaint concerning a part-time teacher who is often absent.

Wednesday, February 14

9am: In previous years, our school has run a popular Valentine’s broadsheet to sell in the playground. This year we’re too exhausted and ground down by events to shower the bonhomie of hearts and flowers.

Another session with Year 8. They are better and more inspired in the morning.

12.15pm: Have own Year 9 group while half the school is at lunch. Give out pound;1 World Book Day tokens. The group is very boisterous and “going rotten” because of the return of a pupil who had been placed in the mentoring unit - the posh name for behaviour modification. His return means everyone is underachieving again.

Sounds of scuffling in the corridor. Try to ignore it in favour of The Highwayman and imagery. But the rattling of my door - which has a porthole through which pupils outside are distracting those inside - makes me fling it open. Surprised, the infamous fall back. They entangle and collapse in a heavy sprawl.

The Year 9s roar and jeer. I swing round to re-establish thoughts about alliteration and the ghostly galleon. All is lost. Dish out detention.

Three pupils own up to avoid a class detention. Loud Mouth tries to take me on, arguing about why she’ll not be present.

8pm: Complete letter to chair of governors.

Thursday, February 15

3am: Wide awake. Feel anxious. Lie for an hour to sort out anxieties. Get up. Take four herbal sleeping pills. Try to sleep.

4.45am: Give up on sleep. Write to a financial compensation scheme. We’re among the millions who took out an endowment mortgage that will not fulfil promises on maturity. Go through home papers, clearing desk.

7.55am: Take deep breaths and swear about working on a slave ship. Call “Never become a teacher” to my neighbour through the car window as I drive off.

9.30am: Year 10 for the first two lessons. They tell me the head has asked aspiring prefects to “grass-up” bad teachers. They tell me that my name did not come up. Apparently I’m strict and kind and expect them to work.

2pm: Year 9 appear. Most are ready to engage with The Highwayman. But Mad Max of the mentoring unit is in hot pursuit of Loud Mouth, who is red-faced, panting and brandishing a bottle of orange drink. The chief combatants in this battle mouth and call across the room to each other. One thug stands with yellow wetness soaking his shirt. “It looks like piss,” he says. The entertainment far outstrips the pleasures of “Bess the landlord’s black-eyed daughter”.

I keep the class in for detention and face brutalising abuse, particularly from Loud Mouth and Mad Max.

5pm: Tell the head that no one should be on the receiving end of such aggression and vile behaviour in the workplace. The head says: “Have you told their head of year?” He skedaddled at 3.30pm. Can I blame him?

6.20pm: Arrive home wrung out. Spouse, also a head of department, puts dinner on the table.

7pm: Attend a concert at my daughter’s school. Faith in humanity restored as the music wafts by.

8.30pm: Visit ailing 75-year-old grandmother, who is due to give a talk to the wild Year 8 tomorrow. They have been reading The Silver Sword, and Grandma fought for the partisans in the Warsaw uprising. She reads their letters and grasps their low self-esteem and neediness.

Friday, February 16 Almost half-term.

10am: Collect Grandma for street-cred, life-saving talk.

11am: Grandma weaves her magic. She is happy back in the classroom. (Tough times don’t last; tough teachers do.) Year 8 falls under her spell. They are enthralled and real education is taking place.

5pm: Carry piles of coursework, marking, profiles and development plans to car.

8pm: Start half-term. Salsa here I come!

The writer, a head of department, wishes to remain anonymous