A principled evaluation for a principled idea garden

Many systems are designed to help novices who want to learn programming, but few support those who are not interested in learning (more) programming. This paper targets the subset of end-user programmers (EUPs) in this category. We present a set of principles on how to help EUPs like this learn just a little when they need to overcome a barrier. We then instantiate the principles in a prototype and empirically investigate the principles in two studies: a formative think-aloud study and a pair of summer camps attended by 42 teens. Among the surprising results were the complementary roles of implicitly actionable hints versus explicitly actionable hints, and the importance of both context-free and context-sensitive availability. Under these principles, the camp participants required significantly less in-person help than in a previous camp to learn the same amount of material in the same amount of time.