by Susana L..
Hi Jake,
Thank you for your input!
I changed the capability 'mod/lti:addcoursetool' on teacher's role, but the teacher is still able to see the "+" symbol and actually create a new tool that shows up on the list of tools (Site administration> PluginsActivity> modules> External tool> Manage tools).
(Am i missing something... or doing something wrong...?)
Thank you,
susana