The title screen gag has the words "30 YEARS AGO..." at the bottom, which is a reference to the Simpsons turning 30 years old on television eleven days prior to this episode's original airing.
The text message Chalmers sends to Skinner during the Grandpa, Grandma song is a reference to Chalmers' catchphrase, "SKINNERRRRR!", with "SKIN" in the first text bubble and "NER!" in the second text bubble (which is obviously correct because Chalmers always says the first part of Skinner's name before he says the second part whenever he yells the name).
The special Donald Trump's First 100 Days in Office is used to promote this episode