[Brenda4562]

I want to leave my child's father when my youngest turns 18 However he will still be in high school

[AK lawyer]

Leaving your child's father would have nothing to do with "abandonment". You may still have to pay child support, however; it depends on the law of whichever state or country you are in.

[ScottGem]

Child abandonment is generally a criminal charge referring to leaving a minor (usually very young) child without adult supervision. So I cannot see you being charged with child abandonment. In a very few states, failure to support would also be considered child abandonment, but in those cases a support order needs to be first issued by a court.