DD just started in YR. I'm a single parent working full time with little contact with other parents who know the ropes. There is a regular newsletter from school telling you what's happening and anything you need to do. BUT.. it doesn't tell you the full story.
As an example we were told to provide a child's shoebox filled with food for distribution to pensioners. I duly did as requested only to find out that the expectation was that I was supposed to cover the box (and preferably something bigger than a small shoebox), get DD to decorate it and add a personal message. When I queried this I was told this was what they always did!
Other than via telepathy how do you pick these things up and what events are equally likely to be poohtraps?