the schools are good, there's no doubt about that (rankings are gamed but that's another discussion) but unless you have extraordinary circumstances or means then paying for college will be difficult. stisd schools are college prep. the curriculum weeds out the ones that can't hack it and you generally get a very smart crop of kids. on paper, this makes the schools look fantastic. high percentages of students going to college, more kids going to top tier schools than most valley districts send in a decade, high number of passing AP scores, etc... all of this makes the schools look fantastic. the downsides are what the students get in return. they are generally college ready, that is true. but you when you have that many bright and driven kids competing, the ones at the top reap most of the rewards. to me, the end goal is college and paying for college. a bright kid is going to get into college, that's the easy part. you have a better chance at money at a public school. a sharp kid at a non-magnet school compared to an stisd peer will generally have a higher ranking percentage, better dual enrollment opportunities, more extracurricular/co-op opportunities, and a shorter day. almost any kid from my graduating class could have been top 10 percent at their home school but they toughed it out. unfortunately the ones with the lowest rankings ended up at panam/utb/tstc/stcc just like everyone else. i was near the top of my class and had scholarship offerings.
tldr -> the juice isn't worth the squeeze imho