Thanks for all the ideas guys! I settled on the brigandine vest, typed out my proposal last night at 12pm, and turned it in today.
Thunder, I'm in MYP right now. In 11th and 12th grade I'll be able to enter actual the actual Diploma Program (although everyone just calls it IB)
As for metal plates, I know for sure that my local hardware store sells steel sheets, around 16 gauge. I also have a few old steel yardsticks, with the ruling on it pretty scratched up and hard to see. I can always cut those up into 1"x3" plates.
My dad is a big astronomy buff, and I have all the materials to do so. Unfortunately I haven't quite taken the same interest in it as my father.
300 hours for a chainmaille shirt? I know what I'm doing for retirement now

(hell if I still have my eyesight I'll try to make a riveted hauberk....assuming I still remember to do it)
My official statement of intent for the project, is to recreate a brigandine vest, in order to test the ease or difficulty of making one, and to determine it's viability as an affordable, poor man's armor during the middle ages. Basically, while the vest is what I personally want to do, the official reason is to make it so to test whether or not a poor man could have been able to afford and utilize it. I recall somewhere that brigandine and leather armor in general was designed with cheapness in mind, so that a poor man at arms could afford it, and so what I'm doing is asking "Was it really all that cheap and affordable or not?".