They're all fully implemented. Some will show up in randomly generated schoolday encounters, for others you need to follow the instructions.
The late one is you must be late to school by not choosing the strait to school and interacting with 3 events and for the bathroom it depends on which bathroom it is but i think the one you are looking for is the bathroom during 2nd period and i gotit by leaving during class and going to bathroom and sometimes 2 bad girls show up