I'm specifically interested in authoring problems in the form of worked examples where one step in a multistep problem (adding unlike fractions, say, or factoring polynomials) is highlighted as correct or incorrect and the student is asked to select an 'explanation' for the rightness or wrongness from a list. (I can supply references for scholarly research validating this approach if anyone is interested -- although, to date, it doesn't seem to have been used with young adult / adult learners.)

At first glance, this probably seems like a pretty simple authoring problem: hard-code the example, set up the reasons as multiple choice, and let the students pick. And, certainly, I can probably use some of the existing randomization features to vary the actual numbers displayed.

But, for any step within a standard multistep problem, there is normally a small set of common error types. And what I would really like is to be able to model/vary the error types as well as just the numerical constants.

I don't yet have a webwork installation to use. I've looked through some of the documentation on the wiki and through some of the forum contents. In neither place am I finding any material talking about the use of correct and incorrect worked examples or self-explanation.

I've got two specific questions:

- Are there any existing problem sets or templates (for any course level, doesn't have to be intro math) that incorporate worked examples and prompted self-explanation?
- Inside or outside of the context of Webwork, can you refer me to any background material on how to model math process errors in an efficient way? Working with math formulas seems like a complicated problem that webwork handles. Intentionally manipulating those formulas to introduce errors seems as if it could get quite hairy quite quickly.

Do, please, feel free to redirect me to another forum or an existing thread if I've misplaced this question. I'm new to the community.

ag