On Monday, May 31st at 11:00 AM there is a service at the Florence American Cemetery just outside of town. If you are here as a visitor or staying in Florence as a student (and I especially recommend young people to visit this place), this is a great chance to see first hand the sacrifices people made in the name of freedom here in Italy during World War II and to honor them. There are usually some speeches and a military band, and many veterans of the war and current service men and women on hand to speak with.
You can reach the cemetery by a "SITA" bus - look for the Via Cassia route - there is a bus stop located just outside the cemetery gate.