Worked Examples in Chemistry – Literature

This post aims to summarise some literature on the use of worked examples in the teaching of problem solving in chemistry. Crippen, drawing from the work of Sweller and others has summarised worked examples as follows (taken from Crippen, 2010, below):

Worked examples are sample problems which have already been solved and provide the learner with a model representation about how to think though complex items (Mwangi & Sweller, 1998). They are intentionally similar in content and structure to the quiz items under consideration for the current study. Worked examples are not scripted, but provide the learner with a knowledge base to understand concepts by demonstrating the necessary steps taken to arrive at a defined solution. They are an especially effective technique for increasing the problem solving skills of novice learners (Kalyuga, Chandler, Tuovinen, & Sweller, 2001), but can also assist in the same way with a more comprehensive audience of learners (Ward & Sweller, 1990). Worked examples also provide an efficient use of limited cognitive resources needed for schema acquisition preferable to mean-ends analysis problem solving methods (Sweller, 1988). Since worked examples are opened only when prompted by the user (learner), we consider this action a self-regulatory behavior.

A Valid and Reliable Instrument for Cognitive Complexity Rating Assignment of Chemistry Exam Items, K Knaus, K Murphy, A Bleckling, T Holme, Journal of Chemical Education, 2011, 88, 554-560. DOI

  • While not about worked examples per se, this paper ties in to the area in two important respects – in considering cognitive load of questions in general and in considering the cognitive components of a question, and attributing a load or rating to these.
  • An example of how a problem could be rated is provided and considers the the concepts and skills and their relative difficulty, and the level of interactivity between the concepts and skills. The rating is found by using a rubric to score the values obtained from this analysis.
  • Correlation was found between the rating of questions and student performance (r = .498), rating of questions and student mental effort ratings (r = .492),

Applying cognitive theory to chemistry instruction: the case for worked examples, KJ Crippen and DW Brooks, Chemistry Education Research and Practice, 2009, 10, 35 – 41. DOI

  • Perspective of literature around key concepts in feedback, worked examples, scaffolding, etc based on cognitive load theory applied to chemistry.
  • Purports that “Instruction that places a heavy emphasis on learning from open-ended problems, those often touted as motivational, is inefficient and ineffective because of its cognitive resource requirements. Instruction that requires students to learn from and interact with structured worked examples of closed-ended problems is consistent with contemporary models of human learning and produces efficient and effective results.
  • Distinguishes between engaging in an activity and deliberative practice in learning how to do an activity. In the former, there is no (cognitive) room for criticism, evaluation of feed-back, etc. In the latter, “the situation is constructed specifically so that one can allocate energy for practice and dealing with feedback, especially disconfirming feedback.
  • Defines worked examples as those which contain: “a) a problem formulation, b) solution steps and c) the final solution“.

Impact of web-based worked examples and self-explanation on performance, problem-solving, and self-efficacy, KJ Crippen and BL Earl, Computers and Education, 2007, 49, 809. DOI

  • This paper describes the use of providing worked examples and self-explanation prompts to improve problem solving capacity in chemistry. Worked examples are used in the context of cognitive load theory, as they can reduce the cognitive load in solving new problems, as learners can focus on problem solving. The paper distinguishes between worked examples instruction for inexperienced learners and problem solving practice for experienced students. The work is based on a prior study which demonstrated that students use extensively worked examples and self-explanation prompts and find them helpful.
  • A quiz is available to students on a weekly basis matching their lecture content. Correct and incorrect results and a grade are provided at the end of each week. The experimental group were provided with questions and three worked examples (designed in accordance with literature guidelines); the experimental group were provided with either worked examples or self-explanation prompts.
  • The results were limited by the fact that there was a small sample size, but showed that there was little difference in exam score between students who were provided with worked examples and those in the control group. The authors suggest that worked examples may be of use in questions that are well structured. The addition of a self-explanation prompt did result in an improvement in score relative to the control group, and the authors argue that this additional component to providing worked examples provide students with context for interpreting examples and activating learning strategies.
  • Project Website: http://crippen.nevada.edu/chemistry/WE_Study/

The effects of feedback protocol on self-regulated learning in a web-based worked example learning environment, Computers and Education, 2010, 55, 1470. DOI

  • Subsequent paper to that described above (2007)
  • Aims to examine worked example feedback protocols that will best enhance achievement and motivation
  • Describes literature into the different types of learners: (1) aim is to successfully learn how to complete a task; (2) aim is to avoid misunderstanding or making an error; (3) aim is to outperform others; (4) aim is to avoid embarrassment compared to others. The results are discussed in the context of these learner types.
  • As above. learners were presented with questions and the option of selecting a worked example/self-explanation prompt.
  • Feedback protocols varied between different groups of the sample of students (184): students received their quiz score and the class average (norm-referenced) or students received their quiz score compared to their cumulative attempts (self-referenced).
  • Results were inconclusive, and authors propose that a mixture of norm- and self-referenced feedback (e.g. by allowing them to toggle between the two).
  • A subsequent paper on this topic is: Scaffolding motivation through the use of worked examples, Journal of Interactive Learning Research in press.

More on the way…