The assignment from school is to gather leaves of the local flora.  Laura and Mary announce their family's planned camping vacation into the "hills" of Minnesota with hope of finding extra special leaves. However, leave it to Harriett, Nellie and Willie (against the opinion of Mr. Oleson) to find a means of turning a short two day hiking/camping/gathering trip into a one-of-a kind adventure. It's like Town Party, Country Party in the great outdoors....only this time there is a river and not a pond to fall in to.  Who will get the most leaves for the the school project?  Why are there Snow Capped mountains on the Prairie?  And which of our campers is a true Wilderness girl?