What are his GPA & test scores? Other qualifications to apply for admission? Even the "least competitive" UC schools can be very competitive!
Your son needs to do his homework! He should have completed his research into universities over the past year and should, by now, have selected 5-10 universities (not more than 4 UCs) to apply to where he has reason to believe he can be accepted. It takes seconds to do a google-search to find the UCs with the lowest standards - and he did not do that. Has he studied schools' websites thoroughly, read student reviews, investigated statistics for previously accepted students, etc? If he cannot or will not do all this, he's not ready for college. Such basic online research skills are expected by age 12-14.
If he's looking for UCs "not too hard to get in," he probably is not UC material. But if he seriously wants a degree in economics, he needs to go to a better school than the very mediocre CSUs.