Ed. Code, § 41601

For purposes of this chapter, the governing board of each school district shall report to the Superintendent during each fiscal year the average daily attendance of the school district for all full school months during (1) the period between July 1 and December 31, inclusive, to be known as the “first period” report for the first principal apportionment, and (2) the period between July 1 and April 15, inclusive, to be known as the “second period” report for the second principal apportionment. Each county superintendent of schools shall report the average daily attendance for the schools and classes maintained by the county superintendent of schools and the average daily attendance for the county school tuition fund. Each report shall be prepared in accordance with instructions on forms prescribed and furnished by the Superintendent. Average daily attendance shall be computed in the following manner:

(a) The average daily attendance in the regular elementary, middle, and high schools, including continuation schools and classes, opportunity schools and classes, and special day classes, maintained by the school districts shall be determined by dividing the total number of days of attendance allowed in all full school months in each period by the number of days the schools are actually taught in all full school months in each period, excluding Saturdays or Sundays, excluding weekend makeup classes pursuant to Section 37223, and excluding weekend and intersession days that generated attendance through an attendance recovery program pursuant to Article 9 (commencing with Section 46210) of Chapter 2 of Part 26 of Division 4.

(b) The attendance for schools and classes maintained by a county superintendent of schools and the county school tuition fund shall be reported in the same manner as reported by school districts. The average daily attendance in special education classes operated by county superintendents of schools shall be determined in the same manner as all other attendance under subdivision (a). The average daily attendance in all other schools and classes maintained by the county superintendents of schools shall be determined by dividing the total number of days of attendance in all full school months in the first period by a divisor of 70, in the second period by 135, and at annual time by 175. For attendance in special classes and centers pursuant to Section 56364 or Section 56364.2, as applicable, the average daily attendance shall be reported by the county superintendents of schools, but credited for local control funding formula purposes to the school district in which the pupil resides.

(c) The days of attendance in classes for adults in correctional facilities shall be reported in the same manner as all other attendance under subdivision (a). The average daily attendance for adults in correctional facilities shall be determined by dividing the total number of days of attendance in all full school months in the first period by a divisor of 85, in the second period by 135, and at annual time by 175.