Believe it or not, this film was inspired by true circumstances. Four minor children, heirs to Cessna Aircraft's family owners, incorporated and purchased public land in 1979. After selling the rights to their story, it was heavily fictionalized and made into this movie.
I would classify this as family entertainment but with the disclaimer the children use mild profanity occasionally. Nothing that a 6th grader couldn't handle, especially taking into consideration the filth children are exposed to these days. It is both a light-hearted fantasy and a glimpse into the nature of entrepreneurship and owning/running a business. (There are some glaring errors, such as no one under 18 can enter into a contract without the signature of a parent or legal guardian. Also, you must be 18 in most states to form a corporation.)
The children give really good performances. I did laugh out loud here and there, although there are plenty of moments the dialogue falls flat, or at least feels forced. The last half takes a more complicated tone, but the ending rounds it out.
Don't take it too seriously. This isn't Chekhov or Shaw. Let it be what it mostly is--good fun.