Enrolled in a summer course at the local college, the summer before starting junior high, so... 1996? The instructors showed us how to format an http query (you had to do it by hand back then) and a few different sites with games and information. They explained hyperlinks for those of us who weren't lucky enough to be familiar with HyperCard (RIP) and, IIRC, webrings and search engines. Then they let us loose.

Most of those first sites I visited were student websites from the Berkeley CS department, and few of them remain. I remember playing Hunt the Wumpus, Colossal Cave Adventure, and the Barney Fun Page. I also remember lots of LotR fanpages, discovering anime, and stumbling on child pornography for the first time (though I didn't think of it in those terms until recently — at the time the model was older than I was!).

After the course ended I bugged my parents until we got a 10hr/mo plan at home that I was allowed to use for 2hr/wk.