In addition to what others have said about CSU students often needing to work part-time, the CSUs to accept students who need to take remedial classes in math, English or both before taking college-level courses in those areas. Systemwide, about 57% of freshmen CSU students needed no remediation in 2013. So, about 43% needed remediation in one or both subjects.
Obviously, needing to take remedial classes slows down graduation or makes it less likely. So, if the kid the OP is working with not need remediation, that’s one less factor to worry about.
You can see the rates of remediation needed for individual CSUs at http://asd.calstate.edu/performance/proficiency.shtml