Ebook: ¿Es duro? (What Is Hard?)

It's easier to name hard things, like rocks, than understand what this characteristic really means. This book encourages young scientists to observe the world around them and discern the features of various familiar things. They'll come to learn that anything that can't be easily bent can be described as hard. The achievable text and colorful photographs support readers in acquiring new vocabulary and a new appreciation for their powers of observation.