The January 6 Premier Crossword by Frank Longo was titled "Calendar Girl's Playlist" because each theme answer was the title of a song containing a day of the week, so we have:
SATURDAYINTHEPARK (23a- 1972 Chicago hit)
MANICMONDAY (35a- 1986 Bangles hit)
THURSDAYSCHILD (43a- 1999 David Bowie single)
AWEDNESDAYCAR (66a- 1977 Johnny Cash song)
NEVERONSUNDAY (76a- 1960 Oscar-winning Melina Mercouri song)
FRIDAYIMINLOVE (97a- 1992 hit for the Cure)
RUBYTUESDAY (108a- 1967 Rolling Stones hit)
EVERYDAYOFTHEWEEK (122a- What there are songs for in this puzzle)
So I guess our eponymous Calendar Girl was more like a "Weekly Planner Girl" as she presents the days of the week rather than the months of the year, which I think is more typically what I would call a calendar. But that's just an issue of semantics that in no way affects the overall fun of the puzzle; besides, 12 theme answers would have been too much to ask for, I think.
Besides the theme songs I spotted lots of answers that were or could have been clued musically, including IRMA La Douce (great soundtrack album), Pop music's Bee GEES, SANTO Domingo (song by Jon Fratelli), Soprano YMA Sumac, POR Favor (yes, it really is a song), Douglas Hofstadter's "GODEL, Escher, Bach" (classical is music, too), Rapper LIL Wayne (ditto Rap), ANTHEMS, "ERI tu" (Verdi baritone aria), Vocalist Vikki CARR, NIAGARA (1990s rock group), Marvin GAYE of R&B music, (Isle of) CAPRI, Singer ROY Clark, TRIO (as in Kingston - you'll see), Saxophonist David SANBORN, (Back in the) USSR, Ella FITZGERALD, the musical variety show Hee HAW, and my own personal favorite musical reference, Scotch and SODA by the Kingston Trio:
And you thought it was just a crossword puzzle!