Bart, Milhouse and Martin all learn they can't trust each other when they pool their money together to buy the first Radioactive Man.
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The Simpsons Season 2 Episode 21 Quotes

(To earn money for his comic book, Marge suggests that Bart get a job.)
Bart: Me!?
Wonder Years Voice: Get a job? Were they serious? I didn't realize it at the time, but a little bit of my childhood had slipped away...forever.
Homer: Bart! What are you staring at?
Bart: Uh...nothing.
Wonder Years Voice: He didn't say it and neither did I, but at that moment, my dad and I were closer than we ever--
Homer: Bart! Stop that!
Bart: Sorry!

(after he sniffed the comic book) It smells like my Grandpa.

Milhouse