Much rhetoric has been espoused and print used to discuss the ways in which SOL tests shouldn't be used, and how the Virginia SOL tests are utterly useless and so poorly constructed that they should be scrapped. Laypersons and experts alike can debate the proper length for a given test and never reach a conclusion. There is no magic rule. However, there are professional judgement and common sense. All standardized tests pose questions as proxies for comprehensive knowledge.
All testing involves the issue of sampling the content area or domain.
That is, whenever someone wishes to test someone on information learned, only a sample of what was taught is included on the test. Classroom tests, norm-referenced tests, the SATs, medical licensing exams, and the ubiquitous driver's test all sample what is expected of the person being tested, not the entire realm of the subject matter at hand. There must be a balance between what is appropriate to judge the level of accomplishment of the student and the amount of time that will be devoted to the process of testing. The length of the SOL tests was based on the recommendations of the Content Review Committees, composed of Virginia teachers and educators, during the development of the test blueprints. Time spent in testing is always a strong consideration when tests are developed.