We survey across generations of work in authorized cheat sheets, and emphasize on extracting generic features for designing one. We construct generic models to address cognitive aspects of learning and focus on the content of knowledge components in the domain of programming language learning. We evaluate the models with real classroom study data and found that the amount of notes on a cheat sheet is associated with gains in students' declarative knowledge, but not procedural knowledge. We also discovered that working in creating new cheat sheets can help students to achieve better exam grades accumulatively beyond and above the effect of their performance in a prior exam. We discuss how these findings can guide the design of technology-based study guides.