Why not before high school? As someone teaching kids, they grasp the concepts just fine at young ages and if the material is presented in a fun and personalized way, they tend to enjoy it more than other subjects (depending on how those are taught).
Actively exposing your child to coding will greatly increase the likelihood they pursue it later on.
Our pricing is as low as $22.50 per hour with a friend, which I consider pretty affordable compared to many extra curriculars!