(CNN) Damien, 13, didn't believe it when he found out his new foster parent would be his math teacher, Finn Lanning.

"The previous two foster homes said that they were stable," the seventh-grader told CNN with a hint of disappointment in his voice. "I didn't think that this one would last either."

Lanning and Damien first met at the beginning of the school year in August 2018 at the AXL Academy in Aurora, Colorado.

The teacher said he knew right away that the boy was special. "He is well-mannered, polite and exceptionally smart," said Lanning, who asked that Damien's last name not be used.

The teenager also faces a lot of challenges.

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