Does your school mix SL and HL classes?

Geniunely curious to know how your school delivers the IB. Do they mix SL and HL classes? Is there an alternative curriculum to IB or is the diploma the only option? In my school SL and HL's are mixed and they also have a "high school" level that basically just see the SL syllabus but don't have to take the final exams, do IA's, etc. When HL material comes up kids doing SL and high school level get to not come to class