Should school days be longer?

The Education Sector, a nonprofit think tank in Washington, DC, recently released a report titled "On the Clock: Rethinking the Way Schools Use Time." The report explores the benefits of increased instructional time during the school day but warns that the quality of teaching is as important as the quantity, and makes specific recommendations for policy makers on how to use school time more effectively.

Though many schools have begun lengthening the school day, some argue that more time in school -- regardless of how it's used -- puts too great a demand on students and teachers, requires too significant an increase in funding, and may not even make much of a difference in student achievement. What do you think?