How long is your trip and what types of things are you interested in (i.e. museums, skiing, historic sites, shopping?) What type of food do you like?

The weather at the end of March in Boston varies - could be cold 30's but we might get some warm days (by warm I mean 60 degrees). I live in NH and was married there 5 years ago April 5th - we had about 8 feet of snow on the ground and skied that morning (Boston snow had all melted) - but this year all the NH snow was gone by mid-February and we had some beautiful spring days by the end of March.....

End of March is still chilly/cold. A warm March day is the exception. None of the spring flowers are blooming yet. Still looks like the end of winter, so you won't get the nice summer photos.

Things to see/do: Fanieul Hall/Quincy Market, Copley Plaza and Prudential shopping, Museum of Fine Art, go over to Cambridge across the river and see MIT and Harvard. Stroll around Harvard Square for eclectic shops and lots of eating places. The Duck Boat tours (if operating in March), the Italian North End for the feel and food of Italy, Newbury Street for block and blocks of shopping and eating.

Skiing at end of March is iffy. It really depends on the snowfall that month, temperature, and if the local areas are making snow. The further north into New Hampshire you go, the better chances of spring skiing.

You will get end of winter - perhaps snow or sleet (I was iced in at Logan overnight once in early April) or yuo might get the beginning of mud season. There are no flowers or leaves on the trees - so your vacation is either primarily indoors - or if you head into the mountains, possibly still skiing.

Not sure where you are from - but if you are looking for spring you need late April or May.