We do not allow teachers to adjust Lexile levels of texts for several reasons. One is that it's very difficult to do -- we'd have to hire a much bigger staff to rewrite texts at different levels. As a small nonprofit, that's not an option for us.
Second, all of our texts are authentic and come from every genre. Offering different versions of the text at a variety of levels would create problems for our copyright agreements. It would also affect the integrity of the writing, so studying author's craft would become convoluted. Imagine having a class discussion or close-read on how Amy Tan's diction affects her tone in the story "Fish Cheeks" when different groups of students have read different words within the same text -- it gets pretty tricky.
CommonLit will continue to add new articles at various reading levels to our library. If you have suggestions for content you'd like to see at lower or higher reading levels, send them to firstname.lastname@example.org.
As a side note, consider checking out our Guided Reading Mode feature which could be helpful if you have readers in your class struggling to read on grade level. It provides a set of scaffolded, low-level comprehension questions that students answer during reading. They receive immediate feedback to correct misunderstandings as they arise. Learn more about Guided Reading Mode here.