Problem Solving in Chemistry

Chemistry students are expected to be able to solve chemistry problems.
On every exam paper, there will be an assortment of problems for students to solve.
Sometimes they do it well, sometimes they do it OK, and sometimes they do it badly.
Often, we give students time before exams to practice answering exam questions.
But how often do chemistry teachers actually explicitly teach problem solving skills?
Often we expect students to "follow our lead" when we demonstrate how to solve particular problems, but do we ever give them a good general framework that they could use to solve any problem they are likely to face in exams?
Most likely the answer is no.
"Surely, by the time students get to the senior years of high school they should be able to solve problems right?" I hear you ask.
While this is a reasonable expectation, the reality is that quite a few can't, just try reading the annual examiners reports and you will get a feel for the kinds of difficulties many students face when trying to solve problems.
So, I've spent some time doing some reading, quite a lot of thinking, and more typing than I'd like, in order to produce a framework for problem solving in chemistry.

You can see the results on the AUS-e-TUTE page on Problem Solving in Chemistry:
http://www.ausetute.com.au/stopgops.html

and a results-only demonstration of the problem solving process in action has been added to the bottom of the amended Dilution Calculations page:
http://www.ausetute.com.au/dilucalc.html

The problem solving page might seem like a lot of reading, but once your students become familiar with the process it is really very quick. It helps them identify potential difficulties BEFORE they actually start doing calculations, ensures they answer the question they were asked and that they check the answer to make sure it is reasonable.

If you happen to teach physics and/or maths as well as chemistry, the method can be applied to these subjects as well.

Because acronyms are useful, I've called this the StoPGoPS approach to problem solving, for reasons that will become self-evident when you read the problem solving page, and I've used a set of traffic lights as a visual aid to recall.

Please feel free to comment on the usefulness of this problem solving model.