Juvenile fiction with alien teacher
I'm trying to remember a book I read in the mid- to late-90s where the teacher is an alien. I don't think it's the "My Teacher is an Alien" series (I suppose that would be too easy). The alien teacher is benevolent and befriends a student. There's a kind of bittersweet ending as the student helps the teacher evade the authorities and escape earth. There was some kind of clue having to do with the name "Sierra Dale Nevada" meaning "mountain valley mountain."
There's another scene I remember, but it's possible I'm getting it mixed up with another book I read around the same time. The student goes to talk to the teacher, but has to wait since he's on phone. The teacher is speaking in Spanish and the student asks him about his dog because he heard him say "perro." The teacher explains that he was saying "pero" ("but").
There's another scene I remember, but it's possible I'm getting it mixed up with another book I read around the same time. The student goes to talk to the teacher, but has to wait since he's on phone. The teacher is speaking in Spanish and the student asks him about his dog because he heard him say "perro." The teacher explains that he was saying "pero" ("but").