This film shows the first mystery ever solved by ScoobyDoo and his friends and how they first met and befriended one another.
* BlatantLies: Shaggy tried to use some to avoid admitting being BookDumb. The list included: being born in a leap year; too tall for his age...
* BookDumb: Shaggy was held back a year twice. He had to admit it when he told his friends he already had a driver's license.
* ExactWords: When they were told they mustn't be seen anywhere near Coolsville High, Daphne emphasized on ''they'' to suggest disguises. [[ComicallyMissingThePoint Shaggy thought she was suggesting using some invisibility serum]].
* FoodAsBribe: During the epilogue, Shaggy offered (and named) Scooby Snacks to convince Scooby to join the gang in further mysteries.
* MythologyGag: Between the epilogue and the end credits, the theme song for ''WhatsNewScoobyDoo'' played, as well as a clip parodying the intro of that series and other ScoobyDoo ones.
* RagtagBunchOfMisfits: The band of heroes were: a Jock, a SpoiledSweet girl, a smart girl, a BigEater and a [[LovableCoward cowardly dog]]. No, not [[CourageTheCowardlyDog that cowardly dog]].
* {{Retcon}}: The origin of the Mystery Machine. In ''WhatsNewScoobyDoo'', it originally belonged to a musical group known as "The Mystery Kids" and was already painted the way most fans got used to see. In this movie, it belonged to Daphne's parents, who kept it for their gardener to use. It was still a plain green van.
* ShoutOut: In the Mystery Machine, there was a HuckleberryHound doll.