Unless you did a significant amount of the design work, absolutely not. "Helping" doesn't constitute calling a project your own.

I don't know what kind of career discovery programs are available to you, but I'd look into taking those to start with. You might also want to take studio art classes in whatever medium you prefer (graphite/charcoal, painting, sculpture, digital media, etc.). The work you submit doesn't have to come from a college course, but it does help to have had feedback from professors and such who know what they're doing.

Also, were you planning to apply this coming fall? To be completely honest, it might be a little late for you to develop enough quality work in time for this coming admissions cycle. You'll be competing against students who will likely have spent months developing each project in their portfolios. I would take a year to do careful research on schools and spend time on portfolio-worthy projects before applying.

Are you going to start architecture from 0? If so, you don't need a portfolio.  You'll need it later when applying to upper division (arch Design 5 -9).  

Depending on your skill level...(be honest with yourself). You will probably want to take a basic drawing class, and another class to develop your craft as a builder (specifically for models) before entering into a summer program. You will be very surprised at the level of talent involved even in their early stage. In my experience at UT Summer Academy, I would say at least half the students were skilled at free hand drawing, and I would guess 80-90% had explored some sort of art/design in the past. 

I am sure it is much different for HS students entering these programs, but adults usually have a good reason for entertaining architecture as a career change, especially in this economy.

@WINTERFRONT ::

I dont understand, having a portfolio is an imperative for applying in M.Arch 1 courses all over .... right?

Yes, for Master of Architecture Degrees in US you will absolutely be required to submit a portfolio of your design work. (The B.Arc may not require one right away for undergrad)

I would suggest some type of design class this year to help you in developing a M.Arc 1 portfolio for the 2012. As stated above, many of the students you will be in contention with will already have strong design backgrounds. Strong portfolios can take three to five months to compile if you are developing projects along the way. 

Good luck!

To the above,

A portfolio is not a requirement at at least 5 schools in the the US, and probably more. The issue with this is that these schools are usually not as highly ranked/respected. Although in architecture, not many people seem to care where you went to school as they are more interested in the portfolio. I will be applying to at least two schools that do not have a portfolio requirement. This is in part because I feel like other aspects of my application are better than my portfolio. However, I would highly recommend making a portfolio because you will want to apply to programs that have specific courses for whatever area of architecture you are interested in.

You will compete with design students. However, it always surprises me how utterly terrible people are at branding themselves. Students who have dent content, but great rhythem and presentation often times do just as well in the admisisons. I feel like there is almost a formula.

A.) Consistent theme (says something about you.)

B.) Show sequential thought process in a few large projects

C.) Show some ability to think loosely/abstract (sketch/sculpture)

D.) Show link between architecture and old career and why interested

All the above should make for a good portfolio even if you are not the most incredible designer right now.