Okay, GiantOne apparently has the southern end of your trip taken care of.

At the northern end, if you can get just south of Wenham to Beverly, you can catch the commuter train from Beverly into Boston. There are several commuter rail stops in towns adjacent to Wenham. The closest stop is the Beverly Farms station, 1 Oak Street in Beverly:
http://mbta.com/schedules_and_maps/r...ons/?stopId=20. According to mapquest, this station is 2.35 miles from Gordon College (
http://www.mapquest.com/maps?1c=Wenh...a=1+Oak+Street). By asking people you know in that area, or looking it up in the Yellow Pages, you should be able to find a local taxicab company that serves the north shore. At 2.35 miles, that's a distance you could even walk, if you don't mind lugging a suitcase a couple of miles.
The commuter rail line from Beverly Farms goes into North Station in Boston. The Amtrak routes down the east coast leave from South Station, so once in Boston you'd have to take the T over to South Station (orange line from North Station to Downtown Crossing, change to the red line, take the red line from Downtown Crossing to South Station).