Everything a middle-grade novel should be. And I'm a sucker for science/biology. I was entirely immersed in Calpurnia's world and could even tell apart her 6 brothers--quite a feat! The writing is strong, sure, and funny. The struggle of a girl in 1899 who doesn't want to hand over her future to a husband/home/children is heartbreaking and dealt with perfectly. Certainly not a pat ending.