Courey said it took him about three months to research, write and, with the help of his parents, edit the book.

“Over the holiday period, he locked himself in his room and just cranked,” said his dad, who’s been investing in stocks for 16 years and currently works for a firm in Waltham, Massachusetts.

Andrew said he owns .00222 bitcoin (about $22.50), which he bought just before Christmas when it was higher, and a little bit of ethereum, but that he’s not buying anymore and would rather own Amazon shares. At the end of the book, he said he’s been reading Brad Stone’s book, “The Everything Store: Jeff Bezos and the age of Amazon,” which is “how I found out about Kindle Direct Publishing,” he wrote.

But Courey has another plan to help him get to $20 million, one that he’s only partially ready to reveal. It involves a mobile app for math flashcards that he aims to scale to $2 million in earnings so he can sell it for 10 times profit.

In the meantime, he’s stuck in middle school.