The curriculum for the kindergarten level children before elementary and or wairian should use the "native language" as the media when children start learning, and then gradually change the language 2.
Programs for preschool or kindergarten. And elementary school should be using "mother tongue" as when a child starts school. Then gradually change to a second language.
The curriculum for children at preschool or kindergarten and elementary school should use "mother tongue" is when the media started Shh shh. He then gradually transforming into the second language.