Goofs

On the uniforms worn by Scoutmaster Dick Van Patten's boys, no two troop members are wearing the same unit number.

During the scene with "the naked Turk" in the bathroom, the Blob has supposedly eaten his dog off screen. When the Turk throws the telephone through the window so he can escape, you can see the dog is gone BUT the Blob is still the same size as it was before it ate the dog.

When Lisa supposedly drives at top speed in a panic through the town in her truck, you can see cars traveling on an overpass behind her truck at twice the speed she is, indicating the filmmakers simply filmed her driving normally and then sped the film up.

In the shot where the kitten's paw has the blob attached to it, a crew member's finger is briefly visible making the kitten's leg go up and down.

Shadows visible during Bobby's party sequence.

The first person the blob devours is Mariane and it's quickly. Next with her husband, Chester, it seems to take hours to fully devour (from night into morning). After Chester, all the next victims are devoured quickly.

If the Blob was not able to tolerate the cold, then it shouldn't be able to handle being in an air conditioned bowling alley.

When Leslie and Lisa are preparing for the party, Lisa asks Leslie "Do you think it's going to be hard to get him over here?" and Leslie says "I don't think so". Then moments later, Leslie turns to Lisa and says "Hey, do you think you'll have any trouble getting Bobby here?" and Lisa reacts confidently "Oh sure, it won't be any problem."