What college should I go to?
I want to be an engineer but, I am not sure what type of engineer...maybe aerospace engineering. The only college I have in mind is Cal-Poly but, I want back-up options in case Cal-Poly does not work out. college engineer
You can fill your first year with common requirements, easily, and by then you'll have a better idea of what you want to pursue. Most people don't declare a major until after their first year anyway; many schools don't let you.
By the end of your second year, you'll probably have taken 3-5 courses specific to your major. If you change to a different major then, you'll be looking at maybe one extra semester (and possibly a minor in whatever your initial choice was), but more than likely you can just fit it in to the next couple years. Even those major-specific courses are probably not actually specific to your major, but apply to a family of related fields (aerospace, mechanical, civil, and chemical engineers probably all take a statics course, and a basic mechanics course that goes beyond intro to physics, and an intro fluid dynamics course). A lot of closely related majors (computer science vs. computer engineering, civil vs architectural engineering, mechanical vs aerospace) differ by just a few courses over the four years.
One question for you first: do you plan to go on for an advanced degree (master's or even doctorate) after college, or enter the workforce straight away? A fair number of positions require an MS or "N years of equivalent experience," and a smaller number actually require a Ph.D.
If grad school is in your future, your undergrad institution is not as critical; a decent state school such as Cal Poly or San Jose State is a fine stepping stone. Even a junior college like De Anza, followed by a transfer to a UC, for example, is a reasonable way to go. Of course, the more you can narrow down your interests, the better you can tune your choice of college/university; a school's reputation in one department need not carry over to a neighboring department. Schools that are strong in most or all science and engineering fields (e.g., UC Berkeley) also tend to be harder to get into.
I'm afraid I can't offer specific recommendations for the terminal-bachelor's case since my own background is in the sciences, and rankings have almost certainly changed since I went to school anyway.
I'm unfamiliar with the universities in California, so I can't point you towards anything specific, but I would recommend you search for a school with a similar program.