Update: Roediger on the mastery value of frequent testing; new material at the bottom of the post.
Here's the short version. At EdTech, Mark Grabe writes:
educators tend to believe that repeated practice has a negative effect on student attitudes and motivation and point to expressions such as “drill and kill” used by influential writers as part of the problem.
This seems to be an item of faith, but there isn't much in the way of research to confirm or deny the hypothesis.
Joel Brondos writes
Nothing attracts more ire from modern educators than asking children to memorize and practice, whether it be their spelling words or multiplication tables. When polled last year , some six of 10 education professors objected to having kids memorize material. These educators, who teach K-12 teachers, warn that practice, homework and direct, systematic instruction turn kids into automatons, stifling their creativity and ultimately dooming their ability to learn. They even have a term for it: “Drill and kill.”
Today at the Eide Neurolearning Blog, the authors post some brain-imaging studies that reveal the ease that automaticity brings. Once you've invested the effort to master a task to automaticity, the brain does not work as hard.
When academic or motor skills don't become automatic, a whole host of problems present themselves. Dyslexic students who have trouble remembering how to form letters automatically, can overload with essay writing, taking notes, or math problem sets (dysgraphia). If math facts, spelling or grammar conventions aren't known to the point of automaticity, then even very intelligent students can find themselves overwhelmed by higher order activities based on these building block skills.
Sebastian Wren has a good basic introduction to the "double deficit" hypothesis of dyslexia (or specific learning disability, and it is called in some circles). The short version again is that some kids have both a weakness in the ability to link sound with symbol (phonological processing) and a weakness in rapid recall (or rapid automatic naming, RAN).
The person I know best with dyslexia explained it thusly to a teacher naive about learning disabilities: "It's like my brain needs to be defragmented. Pulling stuff up takes longer than it should. I can feel the hard drive whirring, but nothing seems to be happening. Then, BING!"
Louisa Cook Moates on the cost of whole-language delusions :
Misunderstanding of the role of skills in competent performance. A most unfortunate legacy of whole language has been the denigration of skill building and skill instruction in the name of holism. The word skills has been repeatedly associated with pejorative terms such as boring, isolated, meaningless, and dreadful in whole-language rhetoric. Skill building is never described as necessary, engaging, satisfying, or enjoyable, or identified as the essential base on which expert performance is constructed. Out on this limb, the field of reading education has rejected major premises of cognitive psychology. John Anderson, a cognitive psychologist at Carnegie Mellon University who won an achievement award from the American Psychological Association in 1995, commented in his acceptance address:
The theory [of knowledge acquisition] implies that acquiring competence is very much a labor-intensive business in which one must acquire one-by-one all the knowledge components. This flies very much in the face of current educational fashion, but...this educational fashion is having a very deleterious effect on education. We need to recognize and respect the effort that goes into acquiring competence.
Competence, he explains, is more than the sum of its parts: it depends on deployment of the right information for the right purpose at the right time. Having at one's disposal a large storehouse of organized and defined information is prerequisite for complex applications of facts, concepts, and skills.
You should also read the section on "What's Wrong With Whole Language".