I found another research.
The topic is "The best age for your children to start learning English".
The research doesn't say how many people answered, but 22.6% think 3 is the best.
The second is 5, the third is 0 (wow!)
After all, 65.8% think that the ideal age for their children to start learning English earlier than 6.
By the way, my cousin's 2-year-old child has already started taking english lessons :P
In Japan, as you may know already, students start learning English in Jr.high schools (7th grade).
Some people think that age is too late to learn a second language and that's the reason that Japanese cannot speak/write English.
People were discussing if students should start learning it at 5th grade. however, the head of Japanese Education Ministry announced that there is no need to do so. The ministry says that studying Japanese, our own language, is more important than studying a second language because a lot of young people today don't speak/write correct Japanese. On the pole on Yahoo Japan, more than half of casters agreed with the ministry. The rest of them say that Japanese cannot speak/write English because they didn't learn it at younger age and it should be changed.
Well, I think I agree with the ministry.
We should learn our own language first, then a second language. (but I still agree that studying it at younger age helps learning it efficiently. but I guess starting at 7th grade or 5th grade is not a big difference :P)
What should be changed is, I believe, the school curriculum and quality of the teachers. They focus on grammers and vocabularies too much and never let them write essays or never let them have presentations. Moreover, some teachers use CD that reads the textbook and the teachers don't speak English, so the students don't have enough chance to listen to other sentences. (This was my experience, so it may have been improved now because many schools have ALT)
I think that is the reason the Japanese students are not good at English at all.
The schools have to change!