<p>I just had a look at Scott Foresman Exploring Mathematics for grades 6, 7 and 8. Editions were from the early 1990s. In the Grade 6 book, square roots were an enrichment exercise. In the Grade 7 book, they had two pages on it with a little on estimation. In the Grade 8 book, they showed an algorithm for estimating irrational square roots - there was considerable coverage and plenty of exercises. I would consider these textbooks average and ordinary. Some of the estimation, critical thinking and number sense was new with the previous revision of the NCTM standards.</p>