the linked article is quite poorly written, but I also had to look at 4 different stories to find some details

When high school students learn about events such as the 1920 Ocoee massacre, the new rules require that instruction include “acts of violence perpetrated against and by African Americans.” The massacre is considered the deadliest Election Day violence in US history and, according to several histories of the incident, it started when Moses Norman, a prominent Black landowner in the Ocoee, Florida, community, attempted to cast his ballot and was turned away by White poll workers.

https://www.cbsnews.com/atlanta/news/florida-board-of-education-approves-new-black-history-standards-that-critics-call-a-big-step-backward/