I've been teaching for over 20 years and every holiday I do the same thing - stay up later, have a long lie in. I'm now at the point where I am sleeping til 9am every day, and that's even with going to bed before midnight! Next week I need to start getting up at 6am again 
Every time I say I won't do it, but then once I'm on holiday all my good intentions go out the window! I have a teenage who sleeps even later than me so no incentive to get up early unless I have booked something. I am intending to start setting my alarm for 8am every day this week, and then 7am for the beginning of next week, so I can manage 6am by next Thursday.
Has anyone got any other suggestions/ fail proof methods that work? In case you haven't guessed - I am NOT a morning person! 