Complex sentence: He then played for the Cambridge Winter Hawks Jr.B hockey team at the age of 14, while he attended Southwood Secondary School until age 15, when he moved on to the OHL Barrie Colts.
Split into simpler sentences: He then played for the Cambridge Winter Hawks Jr.B hockey team at the age of 14, while he attended Southwood Secondary School. After that at age 15 he moved on to the OHL Barrie Colts.