My son attends a highly competitive private prep school. He will take the most rigorous classes for 9th grade available in his school: Human Geo AP (they also offer World History AP that is probably more difficult), CS Principles AP, Geometry H (he took Alg 2 H in 8th grade), Chemistry H, English H, Spanish IV H, Band. He has been studying CS in another institute for 4 years (and plan to continue through HS), he already masters in Scheme, Java, and is working on Phyton.
@momofsenior1 is right, there are many interesting options besides the Ivies for CS and AI: CMU, UIUC, UT Austin, Purdue, GT, Michigan, and of course MIT and Stanford.