Your model class of 12 nationalities is seated in a classic, shallow horseshoe shape. It is day one of English summer school and you are about to leap into the irregularities of English idioms. Hold your horses. The students are physically and culturally jet-lagged and you have just landed the lead part in the longest act of your life. How are you all going to survive?

The students are here for just a month or so and time is limited. However, before you teach them the difference between the active and passive voice, they need something far more basic. Lesson one should address the unfamiliar and shocking truths about living with a host family in Britain.

Whatever the level of the student, a useful phrase to get them through their first few days is “How interesting”. It does duty for all manner of situations and can mean “boring”, “horrible”, or, in all sincerity, “of interest”.

Boiling hot. Freezing cold. No, I am not talking about the proverbial weather but British plumbing arrangements. Countless students are scalded every year in unfamiliar bathrooms. Talk about it and empathise.

As for nutrition and diet, an evening spent in front of the television is enough to testify to our national obsession with screen cuisine.

By all means, let students supplement their screen diet with a helping of Mr Bean. It may not be to their taste, so teach them how to make a safe retreat. A phrase such as “Well, I must write a letter” will allow students to retire without causing offence.

Crossing the road in a country with traffic flowing on the left can be highly irregular, if not fatal, for some visitors. Teach them the relevant parts of the Highway Code.

Once you are confident that your class can cope at home and in the street, you can return to the English lesson proper. However well-resourced the school is, always be ready to prepare your own material. A homemade tape seasoned with the wayward vowels of your flatmate might just energise the whole class.

Whatever the lesson plan, always have something up your sleeve. If an activity is not working, adapt it or do something else to animate the scene. If the course book seems dull, try to personalise the lesson. Use your own CV and embellish or edit according to the mood. Give copies to each student and get them to interview you for different jobs. This may be painfully relevant to those who are still without a teaching contract for the coming academic year. Students usually enjoy this glimpse into your private life. I rarely go for the unexpurgated life history, unless I wish to divulge my telephone number or other particulars.

Unless you wish to bump into your class when buying underwear at the MS summer sale, try going away at weekends. Total immersion can be taken too far.

If you do decide on a day-trip with your students, be under no illusions that it will be a day off. Make sure you know the area well, to avoid the humiliation of getting lost. Whether in town or county, head counts every two seconds are imperative. Remember, an errant 17-year-old in the classroom can behave like a criminal at large in town. Do not underestimate your awesome responsibilities. I once took 20 Spanish students to London. They dawdled merrily down Oxford Street in a steady stream. They then branched out into different shops and soon merged into the general pedestrian flow.

“Don’t bother coming back if one student goes missing,” I had been warned.

Giving students the chance, or hazard, to experience British life is, of course, commendable. For a mini-trip send them to the nearest supermarket to check out the foreign food section. Teach them our quirky custom of pricing fruit per piece and not per kilo. One Thai student happily piled her basket with imported Asian fruits only to find instead of 50p she had to pay Pounds 5.

The July course over, August should be a toddle. You have rehearsed everything. But beware of students who repeat the programme - they know the contents of your entire wardrobe, not to mention what is up your sleeve!

Rosalind Batten teaches English to foreign students in Bristol