If you plan on staying in Manhattan for some time, there are many types of classes you can take, as you can imagine. The offerings are way too numerous and varied to cover here, but include continuing education and extension courses at famous institutions of higher learning like New York University, Columbia University, the New School, and the Juilliard School of Dance, Drama, and Music; classes and lectures at the 92nd St. Y and many other neighborhood organizations serving the community; cooking classes at any of several cooking schools in Manhattan; martial arts classes; yoga classes; classes in religion at any of the numerous places of worship in the borough; etc., etc., etc.
See the Districts articles for more listings.
roosevelt island
Roosevelt Island (http://www.rioc.com/) is an elongated island in the East River between Manhattan Island and Queens. Originally a cattle farm, over the years it has had various names and uses, including as an asylum and a quarantine hospital. Today called Roosevelt Island, it is the home to several thousand New Yorkers who like its calm ambiance and connection to Manhattan. The island offers excellent views of the Manhattan skyline, particularly at the Meditation Steps, just north of the Tramway stop, and Southpoint, a newly-created public space at the southern tip of the island, accessed by one of the riverside promenades. The island also affords one of the best views of the city's 4th of July Fireworks displays when they take place in the East River for the past two years they have instead been shot off from barges in the Hudson River; in such cases, get to the island very early, or you'll find that the seats are sold out.
There are two ways to access the island from Manhattan. The most popular way for tourists and certainly the most scenic is to take the Roosevelt Island Tramway, an aerial tram which crosses over the stretch of the East River between Manhattan and Roosevelt Island next to the Queensboro Bridge, offering splendid views of the skyline along the way. You can board the tram on Second Avenue at 59th Street in the Upper East Side; the one-way fare is $2.25; MetroCards accepted. The second option is to take the subway; the F train makes a single stop on the island, connecting it to the Upper East Side and Midtown to the west and Queens to the east. Additionally, a road bridge connects the island to the intersection of 36th Avenue and Vernon Boulevard in Queens, allowing you to drive, walk, bike, or take the Q102 bus to the island from Queens.