Betsy-Tacy and Tib again, this time as seniors in the class of 1910 in the town of Deep Valley somewhere near Milwaukee. Big sister Julia is off in Europe, studying singing. And the old crowd experiences other changes and displacements. Betsy at last conquers the heart of hard-working, busy Joe and spends a happy year turning 18. Romantic interest for most of the girls, but mainly for Betsy and her close friend, Tacy, who looks as if she might be persuaded seriously to consider a grown-up man. Nothing here to upset anyone, and for the loyal followers.