What do you mean "banning?" It is not federally mandated.
The first sentence says "Gov. Scott Walker's proposal prohibiting the state superintendent from forcing local school districts to adopt Common Core academic standards is up for a vote".
The two descriptions of the proposal are mutually exclusive. They both can't be true. The proposal cannot be both a ban and a prohibition on enforcement.
(Of course, given that this is the media we're talking about, it's entirely possible that neither is true).