The gang reads their radio station review in the school paper. Later, they find an old school newspaper of Mr. Belding from when he was in high school. However, despite these events occurring 20 years apart, the same newspaper is used in both scenes.
When Zack and Screech discover the radio station, they pull sheets off equipment and uncover a record player; the needle is sitting on its rest. When Screech plugs in the power cord, a close up shot of the record player shows a record beginning to spin and the needle is now on the record. A cut to a medium-length shot shows the needle is back on its rest and the record is no longer spinning.
The radio station has been abandoned for 20 years, yet there is not a speck of dust anywhere. So the janitorial staff has been cleaning abandoned equipment for 20 years rather than doing the more sensible thing of removing the unused equipment and re-purposing the valuable space for some other use.
When Zack reads the old paper, he mentions that the picture of mooning is on "Page 3 and 4". He then opens to and looks at a two-page spread. In a correctly paginated newspaper, pages 3 and 4 would be on opposite sides of the same sheet of paper.
The radio station has the call letters KKTY. These call letters are actually assigned to a station in Wyoming.
The flag in the radio station is hanging incorrectly; the blue field should be in the upper left corner, not the upper right. This mistake is common in both Hollywood and the real world.
Zack and Screech plug in the radio station console for the first time in 20 years and it turns on instantly. High power electronic equipment in the 1960s used tubes rather than transistors, and would require considerable time to warm up before functioning.
When Slater gives Zack the money that he wants to donate, you can see that he has no money in his hands at all.
KKTY was shut down in 1968. However, when Zack and Screech reopen the room there is a poster on the wall of The Doors' album L.A. Woman, which was released in May, 1971.
On her radio show Jessie calls the Bayside School District irresponsible for threatening to tear down The Max if Max doesn't pay back the $10,000 in back rent he owes . Max is the one who was being irresponsible by not paying his rent on time.
Kelly and Jessie dance during Slater's sports report, despite the fact that it's radio and no one listening could see them dancing.