The challenge for most kids is not the length of time of the official classes.
The Challenge is that some kids are getting in vans at 630 to get to school
Most schools end at 3 - 3:30
The challenge is that a lot of the schools because the teachers can not teach, have classes after school.
I had a Pratom student who started class at 730. His parents drove and picked him up.
Finished regular school at 3
Then I had an extra class from 3-4. Then another class from 4-5.
Homework is not an issue if done right. Hell all of us growing up had homework. If done right and mom or dad can help it is the only way these kids will learn anything by doing the homework. Also for most kids homework is the time to play their favorite game CAW PEE
Pratom 6, Mat 3, and Mat 6, the kids get hammered.
First, the school says that Somchai has to stay and have an extra class for ONET (yes, schools still do it. Do they put up the advertising banner that says we had 15 students score high on the ONET test to see how good we are?)
Pratom 6 and Mat 3: They then have extra classes to prepare for the Mat 1 and Mat 4 entrance exams. Mat 6 students are getting ready for TCAS, so yeah, they have a lot of time to spend learning how to prepare in 6 months for something they should have been preparing for 3 years.
Add to this that if the parents have the money the kid also does at least a couple of hours a week at least of tutoring.