Eric A. Jenkins & Robert Siegler 
How Children Discover New Strategies [PDF ebook] 

This well-documented book divides the process of constructing new problem-solving strategies into two parts: discovery of the new strategy, and its generalization to new contexts. By using a trial-by-trial analysis, the authors are able to identify the exact trial on which the new strategy is first used, the circumstances that lead to the discovery, and the generalization of the strategy beyond its initial use. These observations disconfirm popular stereotypes of the discovery process and provide important insights into the nature of long-term learning and strategy discovery.