Compared are the US DVD (Unrated Directors Cut) and the Japanese DVD (Extended Version).

With "Class of Nuke 'Em High", Troma points out a cery serious subject one more time: the consequences of radio activity and the people in proximity. In this case, the sword of Damocles of this invisible threat if floating over a school that has been contaminated by radioactive material. Like in "Jaws", the people in charge try to cover up the incident as good as possible and close their eyes from the long-term consequences for the upcoming students. As a result, a monster is being created - similar to Ishirô Honda's "Godzilla". It could be considered the American way of dealing with Hiroshima trauma. But violence at school, lots of pressure to learn und the way of how to handle drugs correctly are the main issues of the pseudo documentary film. Despite the very serious and sophisticated subject, there are a few humorous moments as well. The love story of two innocent teenagers in the chaos of this odd and surreal scenario brings a little warmth to it and makes one almost forget about the horror and terror.
Finally, it is safe to say that there hasn't been a movie that deals with radio activity as intense as "Class of Nuke 'Em High" since "Schindler's List".

The most common version of Class of Nuke 'Em High is the "US Unrated Director's Cut". In the US, it has been released on DVD by Troma. In Japan, a longer version has been released on DVD. This so-called Extended Version is probably an earlier version of the movie which might have been released on VHS in several countries, too. The Extended Version contains several plot scenes possibly remmoved for pace reasons. Some of those scene are available on the US DVD as bonus but not all of them.
The Danish DVD by Midget Entertainment contains the Extended Version as well but it is a bit shorter. The reason for that is the music which continues playing after the end credits while the screen is just black.
The US DVD contains the US Unrated Director's Cut. In other words: it contains the shorter version of the movie.

The US DVD and BD both contain the following scenes as bonus:

-Cramming And Ramming (cut #6)
-Saturday...Night? (cut #8)
-Cretin Chameleon (cut #10)
-Contamination The Extended Mix (cut #13)
-Hoop Screams (cut #11)
-Lab Rats (cut #12)
-Two Pair (cut #14)

[00:02:13][00:02:19]

Extended shot of the workers running around in panic during the alarm.

67.33 sec (1:07 Min.)


[00:05:35][00:04:33]

Missing dialog during class.

Greg: "Old buddy, lend me five bucks."
Warren: "You are ridiculous."

Lehrerin: "Calm down."

Greg: "Wait till Eddy gets here. He'll lend me some money."
Warren: "Eddy can't. He's out cutting class with what's her name?"
Greg: "Oh Beaver pudding."
Lehrerin: "Just answer. Where your name is call. Edwards. Franklin. Ross. Heril. Heril!"

25.87 sec


[00:10:45][00:09:18]

The couple retreats to the basement. The school bell rings.

Warren: "That's the eleven o'clock bell already? No?"

He looks at the watch and throws the pie in his hands in another student's face.

14.07 sec


[00:11:06][00:09:25]

They kiss until their look falls onto the wall. Nuclear slome is dripping from the walls.

When they jump on the mattress, the US Unrated Director's Cut is back in the saddle.

Extended shot of the sign in the US Unrated Director's Cut.

US Unrated Director's Cut: 0.90 sec
Japanese Version: 38.40 sec


[00:16:02][00:13:43]

Further scenes during the pie sale. A couple eats some pie in the cake, one of the cretins grabs some food from the buffet.

30.43 Sek.


[00:21:22][00:18:33]

Shot of the cretins on their bikes.

Followed by more dialog during class.

Eddie: "You gotta start studing Crissy a little more and school a little less."
Warren: "Leave Crissy out of this."
Eddie: "See you wouldn't be so uptight if you getting laid occasionally."

Warren grabs Eddie.

Eddie: "What I say? What I say?"
Warren: "You gotta lay of Crissy and I mean it Eddie."
Eddie: "Alright. Alright. It's just, she is a bad influence on the other girls. They won't show up unless she's there."
Warren: "I can't help but no one trust him and everybody thinks he's such a sleaze."
Eddie: "A sleaze? I don't belive. They must be on to me. I got em graduating. So come on. Are you comming or what?"
Warren: "Alright if that means that much to you, I go."
Eddie: "Alright."

46.03 sec


[00:28:16][00:24:40]

Additional scenes of the party. Mostly dancing teenies with Eddie and Greg. They unsuccessfully try to hit on girls.

59.50 sec


[00:38:14][00:33:40]

Japanese Version:

Cut to Eddie and Greg.

Warren: "Crissy, you know something? Except of the bad gras on saturday night. I really had a nice time."
Crissy: "Saturday? Saturday? Warren, I don't even remember going out with you saturday night. Did we have a good time?"
Warren: "What?"

Crissy laughs at him in order to point out it was just a joke.

US Unrated Director's Cut:

Crissy kisses Warren.

US Unrated Director's Cut: 3.03 sec
Japanese Version: 23.20 sec


[00:46:16][00:41:20]

Japanese Version:

The cretins are laughing. Judie shows up.

Gonzo: "Who's that?"
Harry: "Isn't that Judie Hollander, the cheerleader?"
Judie: "Hold you boner baby. Well, hello Harry. Pilton French ticklers."
Harry: "What's a French ticklers?"
Cretin: "Well, let's say..."

Then cut to the window of Warren's room.

US Unrated Director's Cut:

Cut the cretins who are still laughing.

US Unrated Director's Cut: 4.83 sec
Japanese Version: 33.93 sec


[00:49:56][00:44:32]

At the hospital, some dialog is missing.

Crissy's mother: "I'm her mother, don't you think I would have noticed. Look doctor, last week Crissy went to a beach party. You think I let her out of the house in a bikini if I thought she was nine months pregnant?"

Cut to Warren and Chrissy.

Warren: "When I got home from school yesterday everything electrical went crazy when I went near it. Then I passed out. I had this dream, that I killed P.."
Crissy: "That's a bizarr dream."
Warren: "Crissy listen, you don't understand. P. was killed yesterday."
Crissy: "What?"
Warren: "What? What if I did it?"
Crissy: "It's ridiculous. It was just a dream."
Warren: "Maybe."
Crissy: "Don't worry. Ok?"
Warren: "Ok."

They kiss. At the same time, green slime is dripping out of Crissy's ear.

The US Unrated Director's Cut contains an extended shot of Crissy instead.

US Unrated Director's Cut: 0.67 sec
Japanese Version: 50.03 sec


[00:52:10][00:45:55]

Warren runs to Eddie who is playing basketball.

Warren: "Hey Eddie, how's it going, buddy?"
Eddie: "Hey stud, how you're doing?"
Warren: "I don't know, I feel pretty lousy."
Eddie: "Still seeing giant boners?"
Warren: "Haha, you're so funny."

Warren tries to bucket but he misses.

Eddie: "At least I can shoot."
Warren: "Hey where did the Cretins get that joint?"
Eddie: "I thought they get it from some guy at the power plant."
Warren: "The power plant?"
Eddie: "Yeah, that's what I heard, besides what difference does it make."
Warren: "Why the hell, didn't you tell me?"
Eddie: "Hey Warren. One night in the sack is not good to make your dick fall off."

The US Unrated Director's Cut transitions to a student instead.

US Unrated Director's Cut: 1.27 sec
Japanese Version: 43.53 sec


[00:53:59][00:47:03]

Japanese Version:

Teacher: "Of course it is. This is a prototype laser designed to explode any radioactive material that's aimed at, like nuclear armours for example. You see a collegue and I have developed its military application."
Eddie: "Can it bend steel with its bear hands?"
Teacher "Shmack, if I would aim this at the radioactive isotopes samples there this whole building would be blown into oblivion and you with it. Now get out of here."

US Unrated Director's Cut:

Different shot:

Teacher: "If I would aim this at the radioactive isotopes samples there this whole building would be blown into oblivion and you with it. Now get out of here."

US Unrated Director's Cut: 12.60 sec
Japanese Version: 27.33 sec


[01:01:15][00:54:02]

Shot of a cat trying to catch a mouse. When the cat is just about to catch the mouse, the cat gets attacked by a mutated rat.

Subsequently, a few working dropping dead or screwing around.

Finally an examination of the school.

The US Unrated Director's Cut contains an extended shot of the rats instead.

US Unrated Director's Cut: 2.46 sec
Japanese Version: 87.03 sec (1:27 Min.)


[01:03:51][00:55:13]

Longer dialog in front of the school.

Crissy: "Don't you think its a weird coincidence, that guys from the power plant are sneakin around here again. Look."
Eddie: "Hey, you wanna know, what's really weird? Judie."

Judie: "Hi, stud. I want you to meet my new boyfriend. Name's Lumpy."
Lumpy: "I heard the Cretins are after you."
Warren: "Yes, so?"
Lumpy: "So? I wouldn't wanne be in your shoes."

31.03 sec


[01:13:55][01:04:46]

The shot of the running students due to the alarm is destinctly longer plus Warren trying to get through.

31.20 sec


[01:18:15][01:08:35]

Extended shot of the cretins destroying the school and driving across the hallways on their bikes.

79.77 sec (1:20 Min.)