Hello, I'm 15 years old and I sail on a lake with light winds (8/10 knots), and I want to know which board is better to buy, a Formula or an RSX.

And I also want to know if anyone knows if formula is likely to be Olympic, or when they're gonna change the RSX.

Thanks

If you are sailing by your own and able to manage sails around 10/11 m I would go Formula.

If you are intending to race and sail with other people on RS:X, then I would recommend the RS:X.
The RS:X is a pretty boring heavy board by itself but its main point is to be a One Design class and thus to race with the same equipment (which is a lot of fun even in small group).

You can also buy an RS:X gear (9.5) and use it on a formula board if you are light enough to plane in 8/10 knts with that. Then you can either buy a RS:X board if you want to race the Olympic class or keep the 9.5 as your small formula rig for windy days when upgrading to a bigger sail.

Thanks! I actually have a 11m2 sail, but I want to race, a do I don't know if RSX is worth the investment

Formula won't be in the Olympics any time soon.

I think it depends a bit on what sort of sailing goes on in your local area. If there is a RSX fleet then best to raced with them,
but if it is pure pleasure you are after then maybe Formula is a better option?
I should state that I'm a bit bias, as I really enjoy FW....

Using an RSX rig on a Formula Board is not a bad option also.

The conditions where you live is a consideration...