- if offering.runnable 
  - if defined? is_teacher
    = render :partial => 'shared/offering_for_teacher', :locals => {:offering => offering}
  - else
    = render :partial => 'shared/offering_for_student', :locals => {:offering => offering}
- else
  = "No runnable for this offering: #{offering.name}"
- if offering.runnable 
  - if defined? @portal_teacher
    = render :partial => 'shared/offering_for_teacher', :locals => {:offering => offering}
  - else
    = render :partial => 'shared/offering_for_student', :locals => {:offering => offering}
- else
  = "No runnable for this offering: #{offering.name}"
Use @portal_teacher instead of is_teacher
Use @portal_teacher instead of is_teacher

ApplicationController defines @portal_teacher is
a Teacher is logged in.