Hello, I'm a young researcher from Russia) I make a research about British school slang in last and this century in Cherepovets State University. Please, write what words you used when you were at school. It's just about five minutes, but you will take part in a real research that is going to be publushed this year. Hope, you are interested)
1. A teacher
2. A crib
3. A textbook
4. A school
5. A lesson
6. Homework
7. A school bag
8. Space time
9. A school canteen
10. A school bathroom 1
1. A friend
12. A date/ to date
13. A work/ to work
14. A father
15. A mother
16. A problem/ to have a problem
17. To eat/ food
18. To sleep/a sleep
19. To communicate
20. A computer
I'l respond, but I think you'll find it disappointing, because for the most part, I used the same words you have presented.

1. A teacher - a teacher
2. A crib - a cheat sheet
3. A textbook - a textbook
4. A school - a school
5. A lesson - a class
6. Homework - homework
7. A school bag - a book bag
8. Space time - (What does this mean?)
9. A school canteen - a school cafeteria
10. A school bathroom - a school restroom
11. A friend - a friend
12. A date / to date - a date / to date
13. A work / to work - work / to work
14. A father - a father, a dad
15. A mother - a mother, a mom
16. A problem / to have a problem - a problem / have a problem
17. To eat / food - to eat / food
18. To sleep / a sleep - to sleep / sleep
19. To communicate - to talk to
20. A computer - (Computers did not exist when I went to school.)
AnonymousBritish school slang
Not all your words are slang and not all of them are used in British schools.

2 and 8 are unfamiliar in any British context, not just schools.

10 is used in American English and therefore, is not British. In the UK, that would be known as a school toilet.

Situations when suggestions 11 to 19 would be used in schools, don't come to mind. They might be possible but, don't remind me of anything during my time in British schools.