DENVER—In an increasingly competitive business world, prospective bankers and executives need every edge they can get. That’s why people like Kashious Vela have opted for a specialized camp this summer, where he will learn about economics, financial markets and theories of international trade.

He is also 8 years old and starting third grade later in the year. He’s unapologetic about why he’s devoting his summer to high finance when many children his age will be playing sports and singing campfire songs.

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