Lesson lenghth (London, Y7-8)

[WonderingAR]

In my day and a different country school lessons were 45 min long for everyone.

Now I hear on a school tour it's 75 minutes (1hr 15 min), then read about Harris secondary and it's 100 minutes (1hr 40min)! Is there no official limit on lesson duration at all?

When I was at school many moons ago we started at 8:40, form/registration until 9, lesson 1 9-10 , lesson 2 10-11, break 11-11:15 lesson 3 11:15 -12:15, lesson 4 12:15-13:15, lunch 13:15-14:00, lesson 5 14:00-15:00, end of day form/registration 15:00-15:15.
In older years you'd sometimes get a double lesson 3/4 usually science, PE , technology, I vaguely remember double English.
Hour lessons go really quickly and none actually start when they are meant to because the students need to walk from their last lesson

In secondary they sit and stare on the screen most of the time

No they don't. You're worrying unnecessarily.