The school is likely not yet concerned because, in an NT context, her reading skills are not out of the range for her age/grade, and many schools are reluctant to identify LDs in young children (often for good philosophical reasons, especially when thinking about the general, non-GT population). I assume she already receives some kind of general education reading support, but since that often takes the form of simply more practice using the same strategies taught in class, it may not be sufficient if there actually is a learning difference. Your description does suggest that there is some kind of underlying concern, primarily based on her own frustration.
I can see a few next options at present:
1. request a special education evaluation in writing. In some states, that will be sufficient to start the process. In others, not.
2. have a private evaluator conduct a comprehensive psychoeducational or neuropsychological evaluation. This is pricy, though your insurance may cover some of it, with prior approval. You'll want to go through your primary care physician for this.
3. start remediating without a diagnosis, with an Orton-Gillingham-derived home program, such as All About Reading/All About Spelling (either one will work), Logic of English, or Barton. Or hire an OG tutor privately, or through a center. Private tutors are somewhat costly, while home programs are not, as long as you have the time to spend 20 minutes a day on the program, and can persuade her to try it. AAR/AAS have a one-year moneyback guarantee, so if she won't engage, you do have the option to return it. (The others may as well, but that's the one I've used personally. I have a reluctant reader/writer, currently on AAS Level 7, the last level, who finally complied with reading/writing activities for the first time after starting AAS.)
The least expensive option is #1, but it might not work, if the school is allowed to reject your request. #3 is the second least expensive (if you use a home program), and has the benefit that OG helps pretty much all children with reading delays, regardless of diagnosis or lack thereof. #2 will probably provide the most information on your child's overall profile.
