Improvised lines. Say what a teacher would say but less to no cursing please.

Say the lines with these particular emotions/characteristics in order:

-Enthusiastic

-Reassuring

-Strict

-Mad

I might cast more than one for this role or you can have two or more roles. It depends on how much you can manipulate your voice to make it sound convincing that two characters actually voiced by one person seemed like two characters were voiced by two different people.

[If you can sing, you can sing a line or verse. This is optional unless I need like a music/singing teacher, then it'll help.]