what is the best school for medical assistant?

None! They are all over-priced "career institutes" that are more of a questionable business than an educational entity! Any school that requires you to fill out an online form to get basic information and won't tell you upfront how much their programs cost should raise a huge red flag for you!!

If you really want to be a Medical Assistant, choose a community college. Not only will it cost a lot less (so there is a lot less loans to pay back), you will earn real college credits that can transfer to a university should you want to return to college later on.

If you are in Moreno Valley, try Riverside Community College: http://academic.rcc.edu/programs/mda/

Just to add to the other response, please be aware that there are ** NOT ** supposed to be too many jobs for MAs (or medical billers or coders) despite what those private overly priced For-profit schools proclaim.  Some of those private $$ for-profit schools are ONLY nationally accredited such as everest and ITT tech which is not even the minumum requirement of regional accreditation.  

If any school is pushy, it is most likely due to that sales representative (though they may be called a "recruiter" or "admissions rep") expecting to receive a commission upon the prospective student agreeing to sign up with the school.

The community college or county vo-tech school are more affordable choices as you seem to realize