According to TV Tropes, the structural aspects of Sakura High were based off of the Toyosato Elementary School in Shiga Prefecture. So, it could be assumed that the school is in Shiga. आप can check it out at the website below.
link Then again, I think that's part of the Kansai region, which would mean the girls would most likely have Kansai accents. Hmm. . .I may have only confused the issue. ^.^