Yesterday on NPR I heard a news story about laws that several states are considering regarding literacy - basically the idea is that if a child hasn't achieved a certain competency in reading by the end of 3rd grade, then repeating the 3rd grade will be mandatory.
It would take writing a small book for me to effectively express my varying thoughts on the matter (and to explore all of the many factors that contribute to a child's success in literacy), so instead I thought I'd touch on a phrase about elementary school education that was mentioned in the story (a phrase which is often thrown around but rarely explained.)
Third grade is when kids go from learning to read, to reading to learn.
As for what this means - basically in the United States, we figure it takes the Kindergarten through third grade years in school to introduce literacy skills and teach kids how to read. I know that in my son's 3rd grade class and my friend's 1st grade class, there is a 90 minute block of time set aside every morning that is specifically for reading instruction. (My understanding is this is related to NCLB [No Child Left Behind].)
Once children move to fourth grade, it's assumed that they no longer need to be taught how to read. Instead, the bulk of the reading they do is for the purpose of aquiring information - thus, reading to learn.
Some educators will say that you can't just draw a line in the sand like that - children in grades K-3 can read for information, and there's still plenty about reading that grades 4 and up need to learn. However I think the general spirit of that statement expresses the belief - in the United States, at least, I don't know much about education in other countries - that we expect kids leaving 3rd grade to have a firm grasp on reading. Once you leave 3rd grade, your formal reading instruction has ended.