As I have said before and will definitly say again, our school system is stuck in the past; in the 1970s at best, in the 1950s at worst.
The idea of students sitting in straight rows while the teacher lectures was great when school was meant to create good soldiers and factory workers. However, while soldiers now need to be quick and adaptable, and factory jobs are rapidly going oversees, the schools are late catch up.
Everyone talks about how the twenty-first century classroom needs to be more authentic, more project-based, but few have found a good way to implement it. Yes, I want students to be good at problem solving since memorizing is pointless in this age of instant information retrieval. However, sometimes teachers just need to teach, and there are basic concepts that students need to learn. And many of these skills are difficult or impossible to learn through projects, discovery, or exploration.
Since there are not enough hours in the school year to do it all, I propose putting the lectures online - on my website for instance - and save the classroom for group projects and hands-on learning. A student can learn the quadratic formula alone just as well, if not better, than in a room full of students. If the teacher is going to speak uninterrupted for half an hour anyway, you might as well put it on film. Let the students watch it on their laptops or cell phones the way they want as many times as they need. Save the classroom for question and answer and true project-based learning.
A mid-project assessment (read: quiz) will reveal any students who did not grasp the content, and the teacher can direct them back to the online lesson and to an after-school help session. Even better, the database of online videos could be so broad that the struggling students could watch a couple of other teachers explaining the same concept but in a different style that might reach the student better.
Students need spaced repetition to truly learn, but there is not enough time in the school day for all of that to take part in the classroom. Put it on the web and let a database track who is watching their lessons.