Mary and the rest of her family are delighted when she is chosen to compete in a big, statewide mathematics competition. Unfortunately, Charles does not have enough money to send her along on the trip so the whole town of Walnut Grove rally around in order to raise the necessary funds for Mary to go and for Caroline to accompany her.
Naturally, Mary is very nervous when the big day arrives but Caroline tells her to do her very best. It turns out that, as far as Mary is concerned, her best isn't good enough when she places second overall, but when she and her mother return home, the town is thrilled that she has put them on the map. Great episode. Good to see Mary getting a little more of the spotlight too.