My High School art portfolio was pretty weak. I met with the admissions counselor and she sent me home for the summer with a project: come back with 50 life-sized self portraits, each using a different medium or combination of mediums. I got in, plus got a scholarship.
Go to a school you’re interested in, get the tour, and talk to the admissions department before applying–that’s why they’re there.
jr, I always like to ask posters what they currently have an interest in getting involved in. Saying design alone is usually too broad to answer the question effectively. Schools can and usually do teach a wide range of types of design but they all have their strengths and weaknesses. Some focus on auto styling, graphic or interaction, others product.
Are you undecided, or do you have a particular interest.
Just as a prospective employer needs to customize their cover letters and portfolio to a particular firm, so do you need to customize your application to the schools you are applying to.