In 1994, the then Music Educators National Conference (MENC), adopted the following music content standards (numbers) and achievement standards (letters).
In 2014, the National Coalition for Core Arts Standards published new National Core Arts Standards for dance, media arts, music, theatre, and visual arts. The NCCAS developed an excellent document detailing their work entitled A Conceptual Framework for Arts Learning.
States have developed their own standards for music education prior to, out of, or in reaction to the National Core Arts Standards. As part of the creation of the new standards, the NCCAS reviewed several states' arts standards including Colorado (2009), Florida (2009), Michigan (2011), New Jersey (2009), New York City (2007), North Carolina (2005), Tennessee, and Washington. A simple Google search will turn up results from other states.