I learned to think critically about what I read from one specific incident. There was a local story about a high-school football game that afterward there was widespread vandalism and high levels of aggression/violence.

I was at that game, it it was all very normal, maybe with higher than average attendance, leaving a bit of a mess. The only way I could imagine the news being written as it was, was that the reporter wasn't there, talked to a few people, and extrapolated making the story exciting. There may also have been a motivation to make a school look bad. In any case, the jig was up for the value of in-black-and-white.