Overall, a great speech. Just a few humble suggestions:
1. Write and speak in the present tense. Don't use words like 'was' and 'were'.
2. "Even last year, my English teacher could never control the level of incessant noise made by disruptive, futile students." I don't think this will go down well, considering that you will be presenting this speech in front of your English class later this year. The joke you made a few sentences prior to this about the appearances of students from your school was okay, but I don't think something as direct as this will go down well.
3. "Is it fair that students from prestigious schools, who already have an in depth understanding of the Year 12 course, are competing against us?" This is a massive generalization, which is more or less inaccurate. I came from a relatively prestigious school, and I can say without any hesitancy that not all students have an 'in-depth understanding of the Year 12 course' prior to year 12. I don't know how much the English teachers at your school know about private school students, but my suggestion is that you change that statement to something more nuanced.
4. "Instead of understanding or at least having a “feel” for our future, we are hardly even given a “dabble.”" This is a very good point. Bravo. I am a bit skeptical as to how tenable the comparison you drew between the Capitol and the VCAA actually is, though. You can probably make a joke about how the VCAA sparks fear within students, but I don't think the VCAA runs anything close to a totalitarian regime.
5. "Now, what if the contestants in the Hunger Games who were using the more difficult weapons were given extra points or rewards?" This parallel sounds a little forced. I don't really see how 'more difficult weapons' can be compared to 'more difficult subjects'. In fact, if one were to use a more 'difficult' weapon in the Hunger Games, won't that increase one's chances of death? I don't know, but something about the analogy seems a little artificial.
6. "In 2011, a perfect score required a person to have taken either Specialist math or a language which scaled over 50." I think it is better if you used 2013 as an example instead. The cut off for a 99.95 last year was, unless I'm mistaken, the highest it has ever been (~211.8 if I recall correctly).
7. "Because of this senseless marking scheme, students can lose imperative marks from their final ATAR score, deterring them from being able to apply for their desired course." This sentence sounds a little awkward. I'd recommend that you use 'crucial' or something along those lines instead of 'imperative', and 'precluding' instead of 'deterring'. Some great points were made in that paragraph though.
8. I don't really see the relevance of the penultimate paragraph. You spoke about the ills of the VCE system in all of your other body paragraphs, and then you suddenly start talking about alternative educational systems. There needs to be a stronger link between the other paragraphs on the penultimate paragraph.
9. "We need to start viewing students as individuals, rather than numbers and statistics." This is true, but what is the alternative? Is there one? There is simply no way of 'objectively' measuring the ability of every student in a given population except by making use of some sort of ranking system. Moreover, just because the VCE uses numbers and statistics to measure intellectual capacity and what not, that doesn't necessarily mean that the VCAA views students as anything less than humans. Even American Express assigns strings of numbers to each of its customers!
Hope this helps and good luck!