If California is like NYC, there is a glut of English teachers.
Does he at least have his initial certification as a teacher? Find out what he needs to do now to get his initial certification and work. For his first job, it may be better if he does not have it. A principal may not be willing to pay a premium for a teacher who has a masters and no classroom experience when they can get a teacher with no classroom experience and a bachelors for less money.
Many teachers starting out, work and do their masters at night. Some exceptions would be TFA, NYC teaching fellows and students who are in 5 year bachelors and masters program. Since a masters is required in many states as a condition of keeping your job, don’t pay an outrageous amount for it. You will not make more money because you went to a more expensive school.
He should also look into getting ether an ESL or Special ed extension (both would be really great).