T...Of course, I tried to cheerlead him, "Of course you are, honey! And you will see all of your friends."...
I so sympathize with you and remember this sort of thing from DD's earlier years.
I have to say though that lying to our DD never helped. She knew she wasn't learning anything and just got annoyed that we didn't believe her - when we were just trying to boost her spirits. Just like when we said things like "the teacher is trying her hardest and wants what's best" she knew that was a lie too and that, in fact, the teacher found her annoying and wanted her to shut up and get all 100% if she was so smart.
Why not just lay it out "OK, I appreciate that you aren't really learning anything and that it sucks... let's brainstorm ideas to make you feel better." Even if you can't do everything you come up with (because of external constraints of the school or whatever) you are at least transferring the locus of control onto you and your DS and away from the teacher.
Teachers hate that, by the way, but it has worked great for us.
