Complex sentence: In 1959, a vocational/agriculture building off California Street was added; the next year, new north wing off the main building housed eleven classrooms and science labs, while old classrooms and locker bays were converted into guidance and administrative offices.
Split into simpler sentences: In 1959, a vocational/agriculture building off California Street was added. The next year, a new north wing off the main building housed eleven classrooms and science labs, while old classrooms and locker bays were converted into guidance and administrative offices.