If you miss the one in the crane room this should help. Do the freeplay mode and build a truck in the bounty hunter aria. Then you need to drive the truck though 5 or 6 rooms to get to the crane room. Drive up the lift on the bottom right of the room slowly until the lift goes up. The minikit should show up. if it doesn't restart.
They are scatterred through the game, My advice is to try gamefaqs.com and go to the minikit walkthru!
There's more than one.
Episode 13 : "The Blue Spirit" .
Blue dies in episode 30 - titled "Wolf's Rain" .
Episode 6
The Season 2 Episode: Telling Time With Blue Season 1: Snack Time Season 2: What does Blue Wanna do on a Rainy Day Season 2: What does Blue Want to do with her Picture
Episode 44
episode 1
The episode was titled "The Earth King" and it is in Book 2.
in episode 18
In the episode prom wrecker
It happened in the "Midterms" episode.