Whats the plot?

Rent the 1945 version. The plot is essentially the same, except without the Rodgers & Hammerstein songs.

"Snozberries? Who ever heard of a snozberry?"

Family is coming of age, parents getting older, children on the brink of being adults. Their experience at the state fair is the marking point of this coming of age. No one is going to be the same after, everyone was affected. Subtle and beautiful film.