How much do suspensions affect admissions?

I was suspended in the 1st semester of 9th grade for climbing on top of the roof. I was a stupid, impulsive 14 year old, and I have grown up since then. I haven’t received any other suspensions since then (I am currently only a junior, but obviously do not plan on getting suspended again). I was wondering how much a single suspension affects your chances of admission to top schools, if your grades, test scores, and extracurricular activities are otherwise excellent? My friends are of the opinion that I have completely wrecked my chances of attending a decent college, but I was wondering how accurate this is?

Explain. I honestly don’t think that would affect this too much

For an offense like that during your freshmen year, I doubt your chances have diminished much at top schools. The offenses that really wave red flags include stuff like drug/alcohol abuse, anything having to do with sexual misconduct, fighting/assault, and academic dishonesty. The closer to your senior year, the worse.

Find out from your GC how your school plans on reporting this suspension and if he/she can vouch for your increased maturity since then.