Is it more important to go to a good undergraduate school or a good graduate school?

The most important thing at any education level is that you do well at a program that meets your training needs and gives you opportunity to do the types of studying, research, and internships that you desire. When considering grad schools, notoriety of the specific program and the person who will serve as your mentor is important. You need to find someone who has similar professional and research interests because a good "match" between student and mentor is the most important thing to being accepted and successful in Grad school. Grad schools consider where you did undergrad, but they look more closely at your efforts to get experience in research labs and real world exposure to experiences related to your field.

If you pick a great undergraduate school and do very well then for graduate school you will have scholarships open to you. My personal opinion is to choose the best undergraduate program because college is where people grow and change the most and at the end of that journey grad school may not what you want in the end. But, if you do well at a great undergrad you will have better options in the future no matter what the path is.

Undergraduate teaches you people skill, where graduate school teaches you science. Both periods are equally important for a perfect career. Please do not artificially devaluate one or another. If you have money issue, put you limited recourse in college and study hard. Finish it in three years instead of four. The you have two choices:

1. Since you are graduate from a stop college, you will easily find a good job. Save some money along the way and find good graduate school (part time). You can also quit the job to enroll as full time.
2. Since you have good college record, asking for full scholarship for you dream graduate school.