For decades, I've been trying to identify a book I read when I was in school, in which a boy and girl take shelter from the cold inside a dead dragon (kind of like Luke and the Tauntaun), and emerge with telepathy and other dragon abilities. This scene was all I remembered. Turns out it was the second book of the Pit Dragon Chronicles, "Heart’s Blood", by Jane Yolen, which I just stumbled across and reread. Mystery finally solved!