To differentiate materials effectively for all students, you can offer various formats and levels of complexity.
What would this look like in a multi-age classroom? 

How do you ensure that students with severe speech and language articulation or receptive or expressive disabilities take appropriate routine assessments? For example a student that struggles with speaking fluently i.e. stutters may be omitted from one minute oral reading fluency benchmark testing. Students with specific articulation errors should also not be penalized for these errors during early literacy screeners and benchmark tests. Our district writes the articulations errors on the Acadience test booklet to avoid such penalties.