Embarassed that I still don't really know how to use the agenda commands
after all this time :-(


I have a bunch of trees that look in part like this:
* Asisgnment 1
** Student A
:PROPERTIES:
:GRADE: 0
:END:
I would like to store a search in org-agenda-custom-commands. I generated
it initially with ~C-c a < m +GRADE="0"~. Now I have tried to store it in
org-agenda-custom-commands with this line:

("F" "Failing Students in Current Buffer Only" tags-tree "+GRADE=\"0\"")

However, this seems to choke, and the agenda is not generated. There are no
error messages in *Messages* so I'm not quite sure what's going on.  Can
anyone see obvious mistakes in my syntax?

Thank you!