This is likely to be because some materials cannot be added to classes as they do not include online activities such as Practice Extra, interactive eBooks, or Workbooks to monitor the students' progress.
Such products give access to resources like audio, scripts, videos, etc. (depending on the material), which can be found under ‘My Library’ after code activation.
The most common materials that cannot be used to create classes are listed below:
- Pippa and Pop (British, American, and Special editions)
- Making Connections
- Academic Encounters Listening and Speaking
- Clear Speech
- Cambridge Exam Trainers
- Cambridge Exam Practice Tests
- Cambridge Horizons Second Edition
- Cambridge Little Steps
- Complete IELTS all Bands
- IELTS Life Skills
- IELTS Practice Tests
- Think 1st Edition