Or you can begin with any of the 21 collections choosing up to 50 items to view per collection. European painting, all 2,000 pieces, is completely accessible. The images appear as thumbnails which can be enlarged, and the fine details studied with zoom capacity for most pieces. The notes accompanying the work are said to be newly written for the site. Through one of its special features the Met provides storage space for saving images you like.
Educational materials are extensive and located in four separate departments and libraries.
Explore and Learn is the place to begin for online adult and family educational needs as it tends to be drawn from current or past exhibits. There is a site wide search function but it isn't the easiest one I've seen. You may find it easier to use Artcyclopedia to search for paintings. Surprisingly for an institution that prides itself on its great traditions, there is no history of the museum to be found online. All in all a splendid example of the seriousness and vitality of the history of art on the net.