Even though I was born in California, I currently live in Mississippi. I am looking forward to moving back and attending college in Los Angeles, but the education here isn't as good as in California. There are fewer Ap classes and only 4 periods each semester. I am also worried that they will admit mostly California residents and not even look at someone all the way in Mississippi.
No, it really doesn't have much impact. There is only a slight advantage that California residents have in applying to California State colleges. Unlike other college systems like the University of Virginia where out-of-state admit rates are about 55% less than in-state rates (15.4% versus 32.5%), at UC or Cal State schools the differential is not that much. Also similar is the University of Michigan where out of state is like 20% and in-state is 23%.
The bigger difference in my opinion would be the cost of tuition.
In-state at UCLA is 13,000 versus 43,000 for out-of-state, an extra 30,000.
Frankly, since you will not get much financial aid from UC or CalState schools as an out-of-state resident, I recommend that you consider the Private College route and run a Net Price Calculator on schools like Occidental, Pomona, Claremont, Pitzer, Chapman, Pepperdine, LMU and USC. Depending on your household income, you may find that going to a private would be less expensive since they have more financial and merit aid to dole out. Also, since privates are actively trying to diversify their campuses, coming from Miss. may be a plus to them.
Another fantastic answer by @CameronBameron as usual. They answered your question really well - I just want to touch on something else you mentioned in your question that you seemed concerned about. You mentioned "There are fewer Ap classes and only 4 periods each semester" and I just want to let you know that actually won't matter in your application. You are going to be evaluated based on what is available to you at your school. If you have fewer AP classes than someone in California that won't be held against you because there really isn't anything you can do about it. What you should worry about is making sure you take the most challenging classes available to you as often as possible while making sure you maintain your grades. Admission officers like to see students who are pushing themselves academically so even if you only had 2 AP classes and a handful of honor classes available for you if you took them all you would OK. Focus on taking those difficult classes, getting good grades, building out your EC profile, and other factors that you can actually control. College applications are stressful enough already - no sense in stressing about things you can't control!
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