North DakotaRecord: 29-15-1 overall, 16-12-0 WCHAHow they got here: After coming within one win of the national championship last year, North Dakota faced the challenge of winning games with a roster greener than a Fighting Sioux jersey. With 13 freshmen and just two seniors, the North Dakota started off sluggish, which came as no surprise. However, the team finished the season with a five-game winning streak and carried that momentum into winning the WCHA tournament championship. They overcame Michigan and Holy Cross to get into the Frozen Four, where they will face Boston College.Whom to watch: Junior Drew Stafford (24 goals + 23 assists = 47 points) leads a balanced Sioux scoring assault, with six players above the 30-point plateau and three scoring more than 40 points on the season. Freshmen T.J. Oshie has scored 45 points on 24 goals and 21 assists and currently rides a six-game scoring streak. Fellow rookie Jonathan Toews has averaged 2.25 points per game in UND’s last four contests. Backing up all this offensive power is junior goaltender Jordan Parise, whose 2.08 goals against average and .933 save percentage make him one of the best goalies in the country.How to beat ’em: Keep the puck away from the forwards. North Dakota’s defense, with three freshman blue liners, can be considered its only weakness, if a group that averages 6-foot-2, 201-pounds while giving up only 2.29 goals per game can be considered weak. They do, however, allow 30.5 shots per game, so an aggressive offense and forecheck, especially on special teams, can neutralize their offensive talents and take advantage of their defensive holes.WisconsinRecord: 28-10-3 overall, 17-8-3 WCHAHow they got here: The Badgers’ highs and lows this season can hardly be matched. They rose to the top of the national rankings in the first half only to suffer a slump when goaltender Brian Elliott went down with a knee injury in a January practice, finally hitting rock bottom when they gave up 13 goals in a sweep at Minnesota State in late February. Since then, the Badgers have regained their mojo. Fueled by a win over Minnesota for third place in the WCHA tournament, the Badgers haven’t given up a goal in three straight games, including the double matinee that was their win over Cornell in the Midwest Regional final two weekends ago.Whom to watch: Keep an eye on Elliott. Two words — lights out. This guy hasn’t given up a goal in over 250 minutes (252:49 to be exact) and will find out Friday if he was chosen to be the winner of the Hobey Baker trophy. Also, watch the fourth line of Nick Licari, A.J. Degenhardt, and Andy Brandt. They may not score goals, but they provide the energy that gets both the crowd and the rest of the team into the game.How to beat ’em: Match their style of play. The Badgers rely heavily on defense and goaltending to win games, and when they run into teams that also play exceptional defense, they sometimes have difficulty mustering the offense to pull out a win. Stacking men on the blue line forces the Badgers to dump and chase, a game at which they do not excel. Above all else, equal the Badgers’ physicality. They play rough, and a team that can fight through that also stands a fighting chance to steal a win.MaineRecord: 28-11-2 overall, 17-8-2 Hockey EastHow they got here: The Black Bears started out hot, winning eight of their first nine games before hitting a rough stretch. That midseason stretch saw Maine go 6-8 over its next 14 games, including a pair of losses to Providence — who defeated the Black Bears twice on the season — and Minnesota-Duluth. But since Jan. 21, the Black Bears have lost just two games, both of them coming against NCAA tournament teams (Boston College and New Hampshire). The loss to BC came in the Hockey East Tournament semi-final, but Maine still earned an at-large bid into the NCAA tournament. Despite receiving the third-seed, it really isn’t a huge surprise that the Black Bears upended both Harvard and Michigan State to get to their third Frozen Four in the past five years.Whom to watch: On offense, senior forwards Greg Moore and Michel Leveille have paved the way for the Black Bears. They both average more than a point a game and have been red hot as of late, together tallying a total of 19 points in their last six games. Moore and junior Josh Soares have both reached the 40-point mark, while Leveille is one point away. Between the pipes, Ben Bishop has had a solid season, especially considering he is just a freshman. The big fella, standing 6-foot-5, is 21-7-2 with a 2.22 goals against average and a .908 save percentage.How to beat ’em: Shut down the power play. Maine has scored a power-play goal in all but 10 games this year and score on the man-advantage more than 22 percent of the time, but the Badgers are perfect on their last 25 penalty kills.Boston CollegeRecord: 25-12-3 overall, 17-8-2 Hockey EastHow they got here?: The Eagles lost just four times in their first 21 contests of the year and appeared to have the Hockey East regular season title all but wrapped up in January. Sound familiar? So will the rest of the story. Boston College proceeded to win just four of its next 12 games to close out the season — a stretch that included being swept at Maine and a loss to Boston University in the Beanpot Championship. The Eagles fell again to BU in the Hockey East title game — the fourth loss to their archrival of the season. In the NCAA Regional round, they stomped Miami to set up yet a fifth matchup of the year with BU. BC finally took charge, pounding the Terriers 5-0 to advance to its sixth Frozen Four in the past nine years.Whom to watch: Senior forward Chris Collins has scored 31 goals and nabbed 30 assists in 40 games and is one of three Hobey Hat Trick finalists. He ranks second nationally in points, points per game and short-handed goals. Junior forward Brian Boyle and senior Peter Harrold were first-team all-Hockey East selections. Between the pipes, sophomore Cory Schneider broke the school record with eight shutouts this year and boasts a 2.03 goals against average and a .930 save percentage.How to beat ’em: Well, the obvious way to win is to score goals, something that neither Miami nor Boston U did in the Regional when they were both shut out 5-0. So North Dakota will have to beat Schneider, and putting the puck home early wouldn’t hurt. The Eagles are 6-7-1 when their opponent scores first.