"When I came in here as a freshman, there were goals set, but our ultimate goal was not to win the national championship that year," said Ciampini, now a junior. "It's just been growing each year."
Mat Bodie and Mike Vecchione also scored and Colin Stevens made 34 saves for Union, a liberal arts college in Schenectady, N.Y., with only 2,200 students.
Johnny Gaudreau, Steve Santini, Ryan Fitzgerald and Patrick Brown scored for Boston College (28-8-4), trying to make its fifth title game appearance in eight years.
Ciampini broke a 2-2 tie on a power play at 6:31 of the third period, tipping in Shayne Gostisbehere's one-timer from the point.
Minnesota 2, North Dakota 1 • Justin Holl scored a short-handed goal with 0.6 seconds left to give Minnesota a victory over North Dakota.
Minnesota (28-6-6) will face Union College in the title game Saturday night. Union beat Boston College 5-4 in the first semifinal at Wells Fargo Center.
Holl scored his first goal of the season, beating Zane Gothberg to the glove side with a shot just inside the post.
Sam Warning opened the scoring for Minnesota with 9:09 left, and Connor Gaarder tied it for North Dakota 32 seconds later.
Adam Wilcox made 36 saves for Minnesota.
Union, N.Y. (31-6-4) vs. Minnesota (28-6-6), 5:30 p.m. TV • ESPN