A fifth of primary schools last year ran Primary One classes almost as small or even smaller than the proposed small-class level, according to enrolment figures on the official school profile lists.
Chief Executive Donald Tsang Yam-kuen this week announced plans to cut class sizes in 'suitable primary schools' to 25 students in their 2009 Primary One admission.
Education chief Michael Suen Ming-yeung confirmed on Thursday that the Education Bureau would simultaneously introduce a blanket cap on class sizes 'somewhere between 30 and 40' in all public-sector primary schools.
Although the bureau currently has no upper limit on class sizes, fire regulations stipulate schools cannot have more than 45 pupils in a classroom at a time.
But close examination of the enrolment figures by Education Post found only 20 schools which ran Primary One classes with 40 or more pupils last year.
They included one school - Good Hope School in Choi Hung - which was running five classes with the legal maximum of 45 pupils in each.