I am relatively little experience with CS but I do know some languages like Python and Java. I can afford both schools, but would likely live at home and commute if I choose to go to SCU. Grad school is definitely something that I want to pursue. Which school would be better for grad school admissions? Which school has more prestige for CS? Which school has better job placement? Thanks for your help! 
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Purdue is definitely a better school for CS, but SCU has the great advantage of proximity to Silicon Valley, so interviews will be cheap and easy for you. What is the price difference between the schools? If you are set on grad school immediately after undergrad, I would probably lean toward Purdue. You might consider that summer internships are going to be a lot easier at SCU, and you might want to work part time and go to school part time (many SV companies have tuition reimbursement, typically around $5K/term)
@TooOld4School Thank you so much for your advice! SCU is cheaper because I have a small scholarship and can live at home. How important is a GPA vs. prestige in grad school admissions? I know I can get a better GPA at SCU.
Nationally, Purdue is ranking #20 for CS, #11 for Computer Engineering, while SCU is #112. Admission to graduate school will depend on your GPA, GRE score, recommendations, interviews, and work/internship/research experience. SCU sends about 9% of its graduates for further education, Purdue around 20%.
As for GPA, I think it is going to depend a lot on how much better you think you will do at SCU. You should look at the GPA/GRE range of target grad schools to get a good idea of where you will need to be. I would also speak with admissions and the respective career centers about it in depth at both schools and get more information. But given the higher percentage of students who continue their education after undergrad, I would expect Purdue would be more oriented toward grad school.