This is my first post so sorry if I do anything wrong but in terms of generally better or “prestige” which is better, debate or speech?
Do what you enjoy…one is not “better” than the other.
Debate or Speech what? Club? Class? Competition?
Club and competition
Different. Debate is all about learning to argue two sides of the argument and articulate well. Speech is more about articulation and presentation. I don’t think one is better than another. I’ve seen excellent speakers in each category. I will say, I think debtate requires a more nimble mind in analytics and that speech requires a presentation skill set. Both are great.
Both require confidence and presence.
For club and competition, I would say debate.
But both are valuable skills and you should pursue whichever interests you most. Enjoying and having fun will lead to ongoing participation, growth, leadership, success, etc. Participating in something you don’t enjoy because it’s “prestigious” usually doesn’t turn out well.
Nothing helps as much as doing something you love, putting your soul into it, and doing it well.
An important thing to remember is that there is no specific EC which will cause AO at highly selective colleges to say “that student participated in X, that makes them a better candidate!” Excellence, and extensive effort in some ECs is weighed more heavily than in other ECs, but not participation.
However, even if mere participation in some ECs would provide an advantage, it would be marginal. Colleges which have a 15% acceptance rate are looking at who you are and at what your ECs say about you, not whether you engaged in this are that particular, more prestigious, EC.
That means that, most likely, the effects of your choice of speech versus debate will not affect your admissions chances, all other things being equal. However, it will have a strong effect on how much you enjoy high school. Engaging in an EC you enjoy will make your life a lot better, which engaging in an EC which you do not enjoy will make your life worse.
Engage in ECs which will result in being able to feel pride in your accomplishments, regardless of whether you are accepted into a popular college.
TL;DR version: don’t choose an EC you do not enjoy over an EC you prefer and enjoy because you think that it will increase your chances of admission to a popular college.