"The study found that the district's Career Ladders program, which educates teaching aides to become credentialed teachers, is producing superior teachers."
More: A teacher road map for L.A. Unified - latimes.com
"There are endless opportunities all over the world for qualified TEFL teachers, but European countries offer the most in terms of short-term contracts over university breaks."
More: Teach English, see the world - Study Abroad - Student - The Independent
the abilities and experience which make someone suitable for a particular job or activity,...
qualified: having the standard of skill, knowledge, or ability ...
Do we have a clear-cut difference between a credentialed teacher and a qualified teacher? Does a credentialed teacher need documents in which there is a convincing proof that s/he experienced in his/her field?