250 Bowery Street New York, NY
If you enjoy photography or just like exploring beautiful photos, be sure to include the International Center of Photography into your itinerary. A list of current and future (as well as past) exhibitions is available on their website.
And if you are interested in professional education in photography, there is a school at the ICP that offers mostly long-term programs, but sometimes there are short-term seminars. Check the program details online.