If you use a diary I recommend googling your local schools term time times and keeping note,it's not full proof but it helps with forecasting potentional dips in business,i also make a clear note of bank holidays,also helps me plan my own holidays and advertising as well.
Today is quiet in Leeds, done a half with a lovely reg and hoping for one more before I finish for the day. This week I've only had 30 minute bookings, 2 years ago I barely did 30 min bookings everyone wanted 1,2 hour bookings.