There is no science available which points to extending school time equals more learning. In fact, what we do know is that what a student learns from in the last hour of day is significantly less than what they learn from the first hour. This isn't exclusive to education though, we also know that job productivity goes down with each passing hour.
Now, we also know that the big summer break is a problem, as the students productivity is lower after than it was before. Removing it altogether isn't the answer, however.
Few politicians ever listen to what educational scientists have to say, and almost none of the those who do are conservatives. Thus, it is no surprise that their "ideas" are utter garbage.
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