Katie Coppens

A melting snowman leads her-of course!-to explore climate change and how to reduce her carbon footprint. The helium balloons at her eleventh birthday party beg questions-naturally!-of molecular structure, weights of gases,and neutral buoyancy. An afternoon making paper airplanes brings discoveries in aerodynamics. Tracks in the snow raise questions of how animals survive the winter. And an afternoon of sledding slides...

Acadia Greene has done science in summer, autumn, and winter. In the fourth and final book of this series, she carries her search for answers into the spring, investigating meteors and mass extinctions; germination and pollinators; parasites, ticks, and Lyme disease; and pesticides and malaria. Finally, looking back through her notebooks, she puts together her scientific inquiries from all four...