My life revolves around family.
I suggest completely omitting this sentence and reiterating how your life revolves around your family in your conclusion

I clearly remember March 2007 sitting at my dining room crying after learning that we would not be able to travel to Florida.
If you clearly remember this day, try and pick a date because March 2007 doesn't really flow.

Little did I know, this was the least of my worries for the weeks, months, and year to come. This was the day I learned my mom had been diagnosed with stage 1 colon cancer, yet at 11 knew very little about what cancer was and quite frankly more concerned about not going to Florida. In the next year I experienced more than a typical 11 year old would experience, or should. I watched the horrors and realities that come with a life of cancer unfold in front of my eyes.This is really good and should be the focuspoint of your essay. Now, all you need is a decent "attention-grabber" and you're set for the intro.

My revision: March 5, 2007 marks the end of my childhood. I said goodbye to the annual family trips to Florida, the fun in living carefree, and the ethereal spirit of my family. On this date, I learned that my beloved mother has been diagnosed with stage 1 colon cancer. In the next year, I experienced more than the typical eleven-year-old should. I slowly watched cancer consume the strength of my mother before my very eyes.(or something along those lines... add some imagery).

I recall going to the center with my mom and seeing the others; pale, bald, and lifeless just sitting awaiting another treatment, day after day. Add some imagery and expand this sentence. Remember, the focus point of your essay is how you've seen more than the avg 11 year old and how you've grown due to what you've experienced.

That year I attended a support group for kids who had parents with cancer. It was upsetting to see a number of young children much younger than I was at the time had a parent in a similar or even more severe case than I did. The group was always upbeat and positive but you could see the looks of pain hidden deep down on the other kids face, because they all knew like I did that cancer was not a nice thing and at any moment your parent might no longer be there for you. My step dad and I visited my mom in Boston every night while she was there for her initial surgery and treatment and although it put a strain on my sleep level and my very little school work, I would do anything to see my mom for just an hour a day. I think you should talk more about how the support group helped you and less about the other children. Make sure to talk about your hardships during this time. Include some description as well to show and not tell your experience.

I discovered how much my family really means to me that year. I took on the role of the mother while mine was temporarily out of commission; cooking dinner and keeping the house spotless, just so she would have one less thing to worry about. I always made sure that I complied with my mom's wishes even though I much rather not scoop the cat box or take out the trash early in the morning, I did it regardless. After numerous surgeries and treatments till mid 2008 my mom was deemed in remission.
Although my mom went through the treatments it did not only affect her, I struggled with the fear of losing the ones I love the most. For this, I sought out help from my friends who I could always talk to, and the help from the support group made me realize that the only resolution to my problem was to spend as much time as I can with the ones I care about because you never know when they will be gone.
This experience changed me in the ways that I try to spend all the time I can among close family and friends, making the most of the time we have together. Time with the ones you love will fade, but strong memories stay with you forever.
Also talk about how you've grown from this experience and how you compare to the average male. (you're more mature now. you don't take things for granted. you accept every opportunnity. etc. ) And basically expand your thoughts and re-edit so that everything flows and ties in with each other