As used in this chapter, the term "supplement" shall be defined as instructional or support services for migratory children funded with Chapter 1 Migrant moneys, and offered by a school district in addition to required basic educational services funded with nonfederal moneys and services required by law funded with other federal or nonfederal funds. Such supplemental services shall be designed and implemented in accordance with service models described in Chapter 1 Migrant annual application instructions and shall meet the supplement/supplant tests appropriate to each model.