Insect Day is coming up at school and Elinor is excited to work on her homemade butterfly costume. Elinor knows a lot about butterflies -- how many wings they have, how many antennae they have -- but she can't remember how many legs a butterfly has. She wants her costume to look just like a real butterfly, so she and her dad take a magnifying glass out to the garden to observe some up close. After finding the answers to her questions, Elinor puts the finishing touches on her costume. But costume-making is thirsty work, and Elinor can't reach her water glass when her arms are butterfly wings. How does a real butterfly drink? She'll need more observations to solve this insect mystery -- and perfect her costume! Sidebars with more science facts and a key vocab word are interspersed throughout, and an activity at the end of the book teaches kids how to make a butterfly feeder.

Based on the TV episode "Butterfly Drinks," written by Jorge Cham and Daniel Whiteson.