|Although every challenge problem is not characterized by all of the following characteristics, most challenge problems are formulated so they
- draw on related or linked knowledge among several concepts, ideas, and/or problems.
- include applications to real-world problems.
- focus on the higher level skills in Blooms' taxonomy.
- require more than following the rules for solving problems; they require evaluating which rules to use.
- elicit student interest.
- recognize the extent of chemical knowledge that students could reasonably be expected to possess.
- use resources that are relatively readily available. (Ask yourself, "Is the objective to solve the problem or to do a library search?" Generally the objective is to solve the problem, although a library search would be appropriate in some classes.)
To begin writing challenge problems you might try:
- using raw lab data as the information students must work with, transform, and reconcile.
- transforming the data from a problem in the text to "raw" or "measured" data. For example, changing rates to time in an initial rates method to determine the rate law.
- including extraneous information in the problem statement.
The structure of a challenge problem should be consistent with the problem solving skills of the students but should challenge students to develop additional problem solving skills. To use an analogy, do not expect students in beginning swimming classes to act as life-guards.
A Continuum of Sequencing to Non-sequencing Structure
If most of the students in a class require closure after separate steps in a multi-step process or if you are just beginning to introduce students to the processes and techniques of active learning, then a sequenced or semi-sequenced structure might be most useful to the students. If, however, you are closing a unit with a challenge problem as review you might want to write the problem with less structure.
Linear Problems vs Branched Problems
A linear problem is a problem whose solution involves a series of transformation that may or may not have to be done in a specified order. For example, determining the percent protein in lobster meat given the necessary reactions and measured mass, volume, and molarity values. Branched problems involve using information from different sources (e.g., different analysis techniques) to answer a question about a particular substance, object, technique, etc. For example, determining the composition and structure of a compound from titration, thermal decomposition, and precipitation data.