NFL players steal the spotlight for lots of reasons. Proficiency in grammar has never been one of them.Mark Saldanha, a second-grade teacher at Elmwood Franklin School in Buffalo, N.Y., decided to use that to his advantage last week, when his class selected tweets from NFL players -- and then corrected them.“Basically, [the NFL players' tweets were] a warehouse of spelling mistakes and punctuation lapses,” explained Saldanha to the Buffalo News.