As you may be aware, the public education of the United States has been something to frown upon in comparison to other countries in Europe, such as the Scandinavian country of Finland which is often cited as it is now for having a good education.
To cut to the point, I believe that motivation is the most important attribute to get kids to go to school in the first place. Having them go to school for 5 days a week for longer than some peoples work hours; the equivalent of a full time job except with lack of payroll or freedom to choose to attend or not. Kids have little motivation to go with these grim truths to the current system of education and they have less willingness to attend as they feel trapped. I believe the school day should be either shortened or a day removed, to solve this.