@Mom2Engineers, one really important thing about applying to Cal Poly: All majors are not created equal. There is a lot of information on this site (and other places) that gives you an idea of the GPA and SAT scores needed for acceptance. Additionally, there are enrollment projections that can give you insight into the number of applicants versus available spots for incoming freshmen:
This is the Freshman profile for the class of 2017. It gives you a general number of how many students applied to and were accepted to each of the six colleges. There’s a pretty big difference from college to college:
https://admissions.calpoly.edu/prospective/profile.html
Sometimes it MIGHT be better to apply to one particular major over another based on simple supply and demand. As an example, I’m a high school English teacher. Many of my co-workers have an undergrad degree in Communications rather than English. Pretty common. If a young student wanted to become an English teacher and wanted to attend Cal Poly as an undergrad, there is a significant difference between the numbers for the two majors even though either could lead to the same career. English had an estimated number of applicants of just over 500 with 85 spots available. Communications had an expected applicant pool of almost 900 with only 55 spots available.
These kind of numbers play out in all of the colleges at CP SLO. Often, there is a closely related major that has more spots with the same or fewer applicants. It doesn’t mean that it is necessarily easier (GPA/SAT) to get into the major with the better ratio, just that it might be based on supply and demand.