Anyone who works as an ALT in Japan is familiar with the following situation:
ALT greets students in genki voice. Students return with similar greeting, in very UN-genki voice.
ALT says, "Repeat after me: Blah diddy blah diddy blah blah blah."
SOME students repeat, "blah diddy blah diddy blah blah blah," while most other students sleep, talk to each other, complete unrelated homework, play with erasers, stare blankly...
And the Japanese teacher? Right, the Japanese teacher smiles apologetically at you and does... ab-so-LUTE-ly nothing.
But then there is Kamei sensei.