(105 ILCS 5/27-22.1) (from Ch. 122, par. 27-22.1)
    Sec. 27-22.1. Summer school - required instructional time. Each course offered for high school graduation credit during summer school or any period of the calendar year not embraced within the regular school year, whether or not such course must be successfully completed as a prerequisite to receiving a high school diploma and whether or not such course if successfully completed would be included in the minimum units of credit required by regulation of the State Board of Education for high school graduation, shall provide no fewer than 60 hours of classroom instruction for the equivalent of one semester of high school course credit.
(Source: P.A. 85-839.)