I understand your frustration and concern for your advanced reader. It's incredibly important to ensure that every student is challenged and engaged at their appropriate level. It sounds like you've been proactive in advocating for your child and seeking ways to support their advanced reading abilities within the classroom.
While it's unfortunate that the current resources and strategies in place aren't fully meeting your child's needs, introducing free textbooks could be a viable solution. These resources often offer a wide range of topics and difficulty levels, allowing your child to delve deeper into subjects that truly interest them and challenge their reading skills, you can find some of them here (https://en.openprof.com/wb/subject:physics)
When approaching the teachers again, you might consider emphasizing the flexibility and adaptability of these textbooks. They can be integrated into the curriculum to provide tailored reading experiences for students at different levels, without adding significant burden on the teacher. Additionally, highlighting the benefits of personalized learning experiences for both advanced and struggling readers might resonate with educators.
In addition to suggesting free textbooks, you could also propose alternative approaches, such as independent study projects or mentorship opportunities with older students who share similar interests. Collaborating with the school library to access additional resources or seeking out online platforms that offer advanced reading materials could also be beneficial.
Ultimately, persistence and clear communication will be key in advocating for your child's educational needs. Keep emphasizing the importance of differentiation and individualized support, and don't hesitate to explore various avenues until you find a solution that works for your child and their educators.