For example, n o one will be able to play football or dance forever.
This will give a better transition between the sentences.
T hat is the ability to think.
Unless you are John Steinbeck (just a joke :), it's generally bad practice to begin your sentences with 'And.'
Actually, I think you should combine that sentence with the previous one:
"However, there is one activity that I believe transcends limitations: the ability to think."
How about that?
And if you are not conscious... well, you wouldn't really care by then.
This sounds too casual. Try to replace it with something stronger, or, instead, I recommend that you cross out the sentence because it seems more of a digression. Also, try to add more content in this paragraph.
but the joy of
being able to teach and guideteaching and guiding the largest team in our school's history is never forgottenalways remembered (this is just a suggestion - i thought varying the words would make the sentence sound better)
They would always know how to think, and I, always remember.
I'm not sure what you mean by this sentence. Try to fix the awkward wording here. If this is your concluding sentence, make it stronger, as this sentence is supposed the wrap up the whole essay.
Overall, it's ok. However, you should elaborate on the activity. Currently, your essay is devoid of details. Try to describe what you did as a captain of the debate team, or what your debate team did. Try to present a specific experience that will encapsulate your contribution to the debate team. This will make your essay more strongly emphasize your role as part of the debate team. After all, the main idea is to elaborate on one activity :]