Regarding the Sept. 8 editorial, "More class hours not the answer": While it's always risky to extrapolate from one country to another, it's unlikely that schools in Japan will benefit any more from changes in its school calendar than the United States has.

More seat time has failed to improve test scores in Alabama, Nevada, North Carolina, Texas and other states that have experimented with the strategy. Researchers attribute the results to burnout on the part of both students and teachers.

What seems to make a difference in academic achievement is not quantity but quality of time spent in school. The trouble is that the former is far easier to measure than the latter. Those who insist on measurement, however, are advised to study more closely the law of diminishing returns from economics.

walt gardner