Principal McVicker mentioning that the school needs a new teachers' lounge is a reference of what happened on the episode "Steamroller" and "Breakdown".
It was pointed out that during the flashbacks, the clip of Buzzcut from "No Laughing" is shown to contain him yelling "scrotum" and "clitoris" which did not appear in the episode. This is actually not a goof because in the original unedited version of the episode, Buzzcut uses these words, which were later removed from the subsequent airings as well as "The Final Judgment" video release.
An explanation as to WHY Beavis' butt was burning was never given.
Harry Sachz is a character who was being shot down in "Nothing Happening," yet he was seen in this episode.
Not only have the words disappeared from the photo, but 'Vocal Chords" is misspelled as 'Vocal Cords'.
This goof occurs when the teacher shows Beavis and Butt-Head the picture of the vocal chords. In the close up view of the picture (compared to the earlier shot), the words that point out the larynx, the trachea, & the vocal cords have disappeared.
How Beavis and Butt-head destroyed the Teachers' Lounge isn't revealed.
To the Goof Pick above. I think it is the "GAG" of this Scene, that a spray can and will kill people but it is totally useless against any insects.
If the bug poison is so dangerous (which it states on the can) how come it can't even kill a simple house fly?
After Beavis knocks the picture of the man holding a fish on the wall It shows the glass broke with the picture in it,Then when Butt-head comes out of the bathroom(after hammering holes into his toilet) it shows just broken glass with the picture gone.
When you see the fly killing spray, the center of the can is black. Then, when Beavis and Butt-Head pass out and Beavis picks up the spray, the center of the can is red.
The man that gives Beavis and Butt-Head ten dollars looks just like the man in the confession booth on a scene in the movie "Beavis and Butt-Head Do America", only with differently colored hair.
reply: Barney sound like Earl from "Cow & Chicken".
The name of the show Beavis & Butt-Head watch was "Barney & Friends".
When this episode was released on DVD, there were a few parts cut out from it:
1 - Beavis and Butt-Head saw the teacher's chair apart right after Beavis saws the first-aid kit.
2 - Beavis and Butt-Head were both trying to lift the teacher's desk to the table saw.
3 - The teacher says "I'm going to kill you two for this!" after seeing what Beavis and Butt-Head were doing.
First time in the series a different Maxi-Mart and clerk are shown.
Butt-Head scaring Beavis by screaming at him is like a reference to the episode "Screamers".
When Butt-head was dialing 9-1-1 and got 4-1-1 the 2nd time, he said he forget the number. However, when Butt-head was having his own experience in "Choke", he told Beavis to dial 9-1-1.
When this episode was released on DVD, a part they cut out was Butt-Head thinking of a bug-zapper and a real one is seen next to him where his though-balloon appeared.
Episode is called 'Underwear' on Volume 3 of The Mike Judge Collection, rather than 'Underware' as listed here.