Cor Ouwerkerk coached many sports at several levels, including basketball, football, gymnastics, rugby, soccer, track and field, and volleyball. Cor excelled as an ACAC coach for five decades from 1968 to 2000. He coached the RDC Volleyball Queens for 25 years, leading them to six undefeated seasons. He won over 3700 games, obtaining a 90% winning percentage over a 30-year period. His teams received 13 consecutive ACAC pennants, 14 ACAC gold medals, eight of them consecutive in the 1980's, and made 15 trips to the Canadian Colleges Athletic Association (CCAA) national finals, winning the 1984 National Championship. Cor was named coach of the year seven times by the ACAC and once by the CCAA.