Each school and each agent that continues as such shall annually renew the school’s or agent’s certificate of approval and pay the required annual renewal fees. Every certificate of approval which has not been renewed by its expiration date shall expire on the expiration date.

14 Del. C. 1953, § 8511; 58 Del. Laws, c. 544; 70 Del. Laws, c. 186, § 1; 75 Del. Laws, c. 122, § 1