My friend and I have been working on a History Day project since October. We passed our school History Day with flying colors; described by one judge as, "The best project here, amazing job." I observed that the judges loved fun and interesting facts as they showed that we knew our topic really well, so any of those would be appreciated.
The war is generally considered to have started on July 28 1914, when Austria-Hungary declared war on Serbia. Prior to that, though all indications suggested otherwise, it was still possible that war would be avoided. AH made demands of Serbia that, though outrageous, would have enabled them to avoid war (for the time). June 28 was when the Archduke was assassinated, not when war was declared. The other allies became involved shortly after AH declared war.
They weren't prohibited from attending due to riots, they were prohibited because the other powers did not invite them. Reasons for this include the view that the revolutionary government was not legitimate, and that the Tsar (who was an ally of the Entente powers & a relative of King George) was executed by this government.
Basically, the armistice was prolonged three times after it was first ratified.
You write very impressively for someone your age these days, stick with it.:)
Small note: I've judged high school-level NHD web projects at the national level in the past (but not this year). Yours is a very well-done website — I especially appreciate that you clearly took time to find very high quality images and didn't just grab the first things that came up in Google Image searches. Good job, and good luck.