My Elementary School was the typical all day one class one teacher. Certain time during the day you go to another class that was taught by another teacher. Art, Music, PE, etc. No lockers.

Middle School we had lockers, and it was 6 classes that we called hours. (Your 6th hour class, 1st hour class etc etc)

High School was the same as Middle School until my Senior year when our school was given Standard Student Attire (a collared shirt and nice pants) and block scheduling. A Day you had 1 3 5 and 7 classes. B day was 2 4 6 8. I was lucky and A day I had 1 and 3 and B day I had 2 and 4. 4 classes and I got out in 3 hours!