Wis. Stat. § 115.977: Contracting; continued eligibility.

(2) A school district may establish bilingual-bicultural education programs by contracting with other school districts or with a cooperative educational service agency. If 10 or more pupils in kindergarten to grade 3, 20 or more in grades 4 to 8 or 20 or more in a high school program are enrolled in a program under a contract pursuant to this subsection, the school district offering the program is eligible for reimbursement under s. 115.995.

(3) The school board shall give any limited-English proficient pupil who has begun a bilingual-bicultural education program in the 3rd grade the opportunity to continue his or her bilingual-bicultural education program in the 4th grade regardless of the number of limited-English proficient pupils in grades 4 to 8. However, if there are not a sufficient number of limited-English proficient pupils in grades 4 to 8 to require a bilingual-bicultural education program under sub. (2), the school board may offer such pupil the opportunity to continue a bilingual-bicultural education program with a program established for limited-English proficient pupils in kindergarten to grade 3. A 4th grade pupil so enrolled may be counted for purposes of determining if there are a sufficient number of pupils for a kindergarten to grade 3 bilingual-bicultural education program.