Resume or explanation? or both?

<p>I only got a 3.5 in freshman year...with a C in math, my worst subject. Now I am fine in math, and I had a 4.0 junior year. The main reason I only had a 3.5 was that I had just moved to my high school from another school district in another state (I don't want to offend anyone, so I won't say which...) and I was waayy behind. I mean hugely. The school I go to now is one of the best and most challenging in the country..the one I came from had very little money and I learned nothing.
Should I explain this in the Additional Info section? Or should I attach a resume detailing my extracurriculars? Or both? Help!</p>

<p>In the additional info section, you can attach a short document to describe this. Although, I'm not sure how many attachments they allow for the additional info section so maybe other CC'ers can let you know about that because its been almost 2 years since i filled out the commonapp...</p>

<p>You can get your GC to mention the transition in his/her rec.</p>