Why do the boys start before the girls (basketball)?

Here's the answer, written by "facefacts" on Minnesota-scores.net:

Wisconsin and Minnesota (hockey) made the decision to join the other Big Ten schools and create a Big Ten Hockey Conference. The remaining teams in the WCHA created the American Hockey Conference. The Big Ten is going to play their conference tournament at the Xcel Energy Center while the AHC will be playing their conference tournament at the Target Center. The AHC agreed to a 4 year deal to do this and it takes place on the same weekend that was traditionally the boys state basketball tournament. Williams Arena will not be used as the boys championship for two reasons - first, it is incredibly difficult for fans to get in and out between games, especially with the big schools and second, Williams Arena may be needed for potential Men's NIT games and/or Women's NCAA games (depending on how the Gophers do). The MSHSL did not want to enter into scheduling agreements with the University of Minnesota with those uncertainties in mind. Instead, they flipped the boys tournament to start before the girls and left the girls tournament as is (the girls will play the semi-finals and finals at Williams Arena and will use Williams, Mariucci and Target Center for first round games). This was the only way for the boys to secure the necessary facilities and keep the 4 day tournament schedule (the girls will be using a 5-day format.)