I have seen in various places that Lucas himself expected the movie to be a children's movie in the beginning. He also said that characters like the Ewok and Jar Jar Binks were added to specifically appeal to children.
Was the franchise intended to be a children's movie from the beginning? Or was it more mature and serious in the beginning, but kind of became more mainstream and children-oriented starting from Return of the Jedi, as some claim?
If it was intended as a children's movie, then its cult status nowadays might be a kind of hard to explain. Maybe it's more like a generation cherishing their childhood/teenage dream memory?