I don’t know what is more of an OMG Fact: that ninjas still exist, or that they're about to become a thing of the past. Now, there is only one ninja grandmaster, Jinichi Kawakami. He is the 21st head of the Ban Family, one 53 that was part of the Koka Ninja clan.
He was trained in ninjitsu as a little kid. He learned how to walk quietly, how to break into a house, how to make explosives and mix medicines, among other skills.
However, his skills will probably die with him. He has decided to not select an heir to pass the clan's secret scrolls to. This means that even though some people might learn a few ninja techniques, the ninja clans of the past will be officially forgotten.