Complex sentence: It hosted the National Basketball Association's Sheboygan Redskins from 1942 until 1951, and was the site of the city's Central/South High-North High basketball rivalry from the building's opening until 2006, when both schools will open large on-campus fieldhouses.
Split into simpler sentences: It hosted the National Basketball Association's Sheboygan Redskins from 1942 until 1951. The building was the site of the a cross-town basketball rivalry between Central/South High and North High from the building's opening until 2006, when both schools will open large on-campus fieldhouses.