In a memorable scene of Sara Zaske’s guide to German-style parenting, Achtung Baby: An American Mom on the German Art of Raising Self-Reliant Children, Zaske sends her 4-year-old daughter Sophia to her Berlin preschool with a bathing suit in her bag. It turns out, however, that the suit is unnecessary: All the tykes at Sophia’s Kita frolic in the water-play area naked. Later that year, Sophia and the rest of her Kita class take part in a gleefully parent-free sleepover. A sleepover! At school! For a 4-year-old! These two snapshots of life as a modern German child—uninhibited nudity; jaw-dropping independence—neatly encapsulate precisely why Zaske’s book is in equal turns exhilarating and devastating to an American parent.