A study of three instructional sequences for developing computer programming expertise in novice learners

Studies show that for many years courses teaching computer programming skills to novices have engendering a general dislike for programming. Other studies have shown that novices learners first acquire surface features of a domain, then undergo a unique reorganization of their knowledge as they develop expertise. Domain experts may therefore teach concepts which seem intuitive to them yet are incomprehensible to novices. The first phase of this study presented identical content in one of three instructional sequences to 34 college students who were programming novices to determine which produced the greatest development of programming expertise. Learning was measured by performance on a Programming Assessment given immediately after the intervention, and effort and difficulty were self-rated during the instruction. There was no significant difference among the groups in Programming Assessment scores, and overall self-rated effort and difficulty of the instruction did not vary simply by rearranging the order in which the major elements were presented. However, instructional units that covered programming syntax skills and structures were rated by all groups as requiring significantly less effort and difficulty than units covering plans, and participants in all groups scored significantly higher on syntax skills and structures than on plans. The second phase sought evidence that the nature and complexity of programming knowledge show reorganization as expertise is personalized in programmers by comparing the fifteen top performing participants on the Programming Assessment with three programming experts in chunking a short program and in constructing the central solution statement to four programming problems. Experts chunked programs to twice the levels and twice as fast as novices, indicating differences in the mental organization of novices and experts. These results suggest that presenting introductory programming concepts in the order of syntax, then structures, and lastly programming plans results in maximum learning efficiency as measured by self-rated effort and difficulty. An instructional sequence that mixes these concepts together can be as effective but increases cognitive load. An instructional sequence that reverses this order leads to cognitive overload and the loss of linearity in the lesson as evidenced by participant comments and effort and difficulty ratings.