(a) The governing board of any school district may establish an early primary program consisting of same-age pupils or any combination of state preschool or child development program, kindergarten, first, second, or third grade pupils, based on an integrated, experiential, and developmentally appropriate educational program. Parent education and parent involvement shall be an integral part of the program.
(b) Observation of a child over time and the use of portfolio material shall be the primary sources of assessment information for making curricular decisions in early primary programs.
(c) Standardized assessment tests may be used for diagnostic purposes only, provided those tests have been demonstrated to be nonbiased, valid, and reliable. These tests shall not be used to deny admission.