How to make students smarter by managing class time

All teachers want their students to do well. However, as humans, not all of them are willing to work hard or smart for it.
The challenge, therefore, is how to improve the result without students and teachers spending extra time.
The answer is Longer sessions and Shorter sessions. Having short sessions mean more frequent sessions. Long sessions mean less frequent sessions. therefore the total time spent overall remains same.

Most sessions (class periods) in schools are 50-60 minutes. For the purpose of this post, we consider short sessions to be 30 minutes or less. Long sessions are 90 minutes or more. 

Shorter sessions

It's been widely circulated that human attention span wears out after 20 minutes. Since humans can't focus for more than 20 minutes, each session should not more than 30 minutes, including the margins for settling in the class.

The above suggestion may be correct for pure instruction based learning - where a teacher stands in front of the board or a projector and disseminates information to students. However, there is a better way. It's longer sessions.

Longer sessions

Research shows that longer sessions lead to deeper learning and create the learning environment which includes more students of varying abilities. That means that even students who generally do not open up, do. 

But, there's a catch:

A long session doesn't just imply a short session stretched three times as long. That would mean jumping into all the problems of attention span because of which we prefer shorter sessions in the first place. When in longer sessions, the mode of delivery can become more inclusive than a one-way delivery in a traditional class. 

Primary reason for the success of longer sessions is teacher creativity. Given more time, teachers tend to try new things depending on the class they are handling. They take the kind of decisions that can't be taken sitting in an office, isolated from students.

Longer periods enable group activities, discussion between students and with the faculty, and cooperative learning. That's the way most humans have been evolutionarily wired to learn - by interacting with each other.

For long sessions of 2 hours or more, giving small breaks of 10 minutes to half hour is not a bad idea as the mind keeps working on the discussion in the break. Break also allows you to build up on the first half of an intense session and go deeper in the second half of the session. 

Drawbacks of Longer sessions

None really except for the fact that if students miss a class, there is just so much more to catch up.

Examples given by the researchers of session times in National teaching and learning forum: "A study done at Philo High School in Ohio found the number of students making the honor roll doubled during the first year of block scheduling. The number of A’s made by juniors and seniors jumped 24%; the number of failing grades dropped 15%. The effect on the school (or learning) environment was positive. Discipline referrals declined 25%-50%, dropout rates decreased, and class attendance increased dramatically.

What do you think about short / long sessions?