Way back when Twin Peaks was first on the air, I, and my other obsessed friends watched with microscopic intensity. One of the things we discovered from context of the shows is the dates that each episode took place. The pilot opens at dawn on February 24, 1989 which is the same date that Laura died. Each episode is about one day in length, though some episodes end well after midnight, still, the following episode picks up after dawn on the same day. The end of season one takes place on the day and night of March 3, 1989 yet ends well after midnight on March 4, 1989. Season two opens later in the day on March 4, 1989. This stands throughout the first season, and well into the second until you get to the episode that has the text that says, "Several Days Later", which makes it harder to determine what days things happen from then on.
February 24, 1989 was a Friday, so the 25th and the 26th were a weekend. Once you know the days of the week, the lack of school attendance on the part of some of the high school characters begin to make sense. Donna isn't skipping school to deliver food for the Meals on Wheels. She's just delivering it on a Saturday. That's not to say that characters aren't skipping classes, though.