Spelling and grammar doesn't have much to do with being young IMO. If anything the more youthful you are, to a certain extent, the more in touch you should be with modern MLA. To prove this go look at Ratsun.net, most of those guys there are at least 30 years of age and that place has some of the worst spelling and grammar on the net.
Edit: And to the OP... I believe the word you were looking for was "too".