my son who is 18 would like to get a visa for China in order to study Kung Fu next October

You can't apply for visa by mail. Since the operation of China Visa Application Service Center in Paris on 14th January, 2011, the embassy in Paris only accept China visa application from diplomatic/service/official passport holders. You have to submit application to the center in Paris, but the center doesn't accept application by mail now.

Detailed Information of CVASC:
Address: 117, Champs-Elysees, 75008 Paris.
Tel: +33-1-79970339
Fax: +33-1-47206328

If you can't come to Paris in person, you can ask someone else to do it for you, such as your friend, relative or travel agency.