Sanchez: "The President has had a little fun with me from time to time, most recently at the Correspondents dinner" "Mr. Obama if you're watching, there's no "s" in the word backwards, that is incorrectly spelled, the word is 'backward,' not backwards"
Obama Tweets:

However, while the above misspelling is bad, it is dwarfed by Obama spelling the word Syracuse when filling out his NCAA bracket, this is what he wrote before being corrected by the ESPN host: (From March 18th)
"Sycasuse"