While the lack of growth seems concerning, from your post it also seems to be directly related to the lack of reading instruction at her level of readiness and ability, throughout the year, in the classroom.
Fortunately, reading is an area in which growth may be facilitated at home. What are your child's reading interests and patterns outside of school? What type of books does she gravitate toward?
Some families make regular trips to the library and/or book store.
Reading with a dictionary nearby or making a list of new or unfamiliar words can help with vocabulary acquisition.
Reading aloud to you in the car, as you drive to activities or on errands, is another strategy which some families use.
Having conversations about what she is reading, taking guesses at predicting what may happen next, developing alternative endings, and discussing the characters (which ones would make good friends, what behaviors/decisions were positive/negative/risky), may be another way to facilitate reading growth.
Because you mention Lexile levels... did you know, parents can look up books by lexile level, online at
Lexile Find-A-Book.