Scunner, sometimes it's the staff in 'certain' places that you have to beware of - ha ha ha. I would be explaining to the teenagers before they go, NOT to expect too much as far as nightlife is concerned and if you take them to any of the bars, stay with them. Point out the plus side of things to do during the day, swimming in the sea or pool, exciting excursions, the markets, going for nice meals etc. etc. Young people, particularly young girls, who tend to look older than they are will get lots of attention so without being alarmist, I would ensure that I was with them or close bye when they are out and about, especially in the evening.