If you are interested in the No. Shore try Plum Islands (Joppa flats) There are some nice sight - fishing opportunities there, not unlike those on the Monomoy Flats. In terms of patterns to learn, try the Clouser (probably the easiest) or the Decevier pattern. These are effective patterns for the areas in which you are looking to fish. (2.0's)
Do not pick the North Shore and the Boston Harbor at the expense of South Shore offerings e.g. Hull Gut, 3rd Cliff, 4th cliff or under the Powderpoint Bridge in Duxbury. There are some cows in this area, however later in the season. The migration really hasn't hit this area yet, although there may be some 2 or 3 year olds who may have got an early jump. Expect the beginning of May to bring the fly rodders out.