(a) A local or regional school district shall excuse any student from participating in, or observing, the dissection of any animal as part of classroom instruction, provided the parent or guardian of such student has requested, in writing, that such student be excused from such participation or observation.
(b) Any student excused from participating in, or observing, the dissection of any animal as part of classroom instruction shall be required to complete an alternate assignment to be determined by the local or regional school district.