At work: When new coworkers and old ones loosen up enough to start talking to each other.
When something that might be embarrassing (or just surprising) breaks the ice so said coworkers start laughing and joking without any harmful pranks or jokes.
When the day goes so well there's little left to do.
When the weather turns sour and everyone's stuck inside talking-which is actually fun.
At School: When you pass a tough test and can relax for a while.
When the teacher has to leave early which gives you more time to do homework or study.
When the teacher just lets you out early (whether you're ahead of schedule or not) so you can do other things.
When the teacher wants feedback and actually encourages criticism so them can teach better.
When teachers let you redo rushed assignments so you can improve a bad score and pass the class.
When a teacher decides you've earned a good grade for effort even if your work wasn't the best.
When the semester is over and you can stop lugging around heavy textbooks and stuff.