My niece just finished 9th grade this past June. She had a lunch period of about 35 minutes, but she wasn't always able to eat because she often had somewhere else to be during all or part of her lunch period. (Speak with a teacher, meeting about an extra-curricular activity, pick up a book from the library, that sort of thing.) I can see where kids scarfing down their lunches quickly and chattering would lead to choking incidents. I think that's true in our office, too - we're under such pressure to get a high volume of work completed that we tend to eat on the fly and hurry back to our cubicles. Maybe not in other offices, though. I did have a previous job where lunch was 45 minutes in length and staff were encouraged to take their full lunch.