On Saturday evening while I was out having dinner I overheard a conversation that sounded like a father telling his daughter (I can't confirm the relationship as I didn't turn around to look at them) never to use Wikipedia because it's not reliable. That conversation could have just as easily been heard in any number of classrooms around the world. Often those conversations are based in a lack of understanding of how Wikipedia works.
A good resource to help people understand how Wikipedia works is Wikipedia Explained by Common Craft uses Common Craft's In Plain English style to explain how Wikipedia works. The video explains how Wikipedia entries are written, updated, verified, and maintained. Watch the video on Common Craft or as embedded below.