The first place to stop would be to stop lowering our expectations of all children. The more the drive standards down to the lowest common denominator in order to pass the greatest number of students each year, the more the lower the bar that the brightest are given an opportunity to achieve. It also lowers the level of language students of all abilities are exposed to, and reduces what they can achieve. I strongly believe in remedial teaching as needed for diverse subjects, but the USA educational systems often target offerings to the lower end of the masses, and do a disservice to the academically gifted and academically challenged in the process. Read the writing of Mark Twain, Frances Hodgson Burnett, and other authors of what were considered children's (elementary school age) books 100-150 years ago. Notice the rich and colorful language in them. Notice that everyone thought that 8-9 year old children should be reading them. Then notice that while we have some exceptions in modern publishing, the general language standard has been simplified greatly on average in children's books. If you aren't exposed to colorful and complex writing, you'll never get better at understanding it.
In the past, many schools also employed more time with the teacher reading novels years above their grade level to children, then verbally discussing it in chunks. This prepares them for later reading them on their own and writing about what they've read, as verbal language comes more easily to most. If you read a chapter a day of the first Harry Potter book to a 5 year-old who really can't read it on their own yet, then talk about what happened in each chapter as you go, and ask them/allow them to describe why characters did certain things, you help increase their own language ability in both comprehension and expression.
Some public schools now frown on this, as they dogmatically stick to the official list of reading levels. Some teachers are simply too overwhelmed by the sheer number of students they must deal with, the other social needs of students they must deal with, and the rest of the modern mess.