The new books dive into variables in chapter 1. By Chapter 3, students are solving thorny inequality problems (it takes 2 chapters to get to these problems in a good algebra 1 book). The sections on decimals are actually just messy variable equations that happen to have decimals as coefficients. And the fractions...oh dear, the fractions.
Etc.
. . .
Pre-algebra was simply a review for students who needed to hone their math skills. I'll write a separate message at lunctime with the details, but the basic idea is that students were given a solid foundation in elementary and junior high math concepts:
Let's practice arithmetic and learn mathematical properties. Let's learn about different counting systems and how to convert between (for example) base 5 and base 10. Let's learn about the number line, and fractions, and negative numbers, and basic geometry, and statistics. Etc..
I honestly don't understand how a student can be led through the new books and understand any of it in a meaningful way (unless a parental unit or tutor is filling in all the gaps). I suppose that these books play a role in the proliferation of places like Kumon and the Mathnasium, which use mathematically correct proprietary curricula.
I see what you are getting at regarding quality and the Dolciani text in fact may be a great review for elementary kids. However, these old-fashioned books would not work well as a pre-algebra text in many places, including our district, as it would be too much review and not enough coverage in preparation for our GT Algebra I and GT Geometry courses. However, I have to admit that I much preferred DS's pre-algebra text (1999 (?) McDougal Littrell) better than DD's "modern" 21st century Univ. of Chicago text, but actaully partly because it provided more sophisticated coverage, including a small section on Trigonometry.
Anyhow, our spiraling curriculum plus proliferation of elementary algebra and elementary geometry topics mean that students enrolling in Pre-Algebra today are supposed to be in a different place than 50 years ago. A pre-requisite to Pre-Algebra is mastery of fractions and decimals. In our district, to get an acceleration to Pre-Algebra in 5th grade (rather than 6th for standard GT) required passing a test that emphasizes mastery of fractions and decimals. After taking this test, DS11 accelerated to Pre-Algebra a couple of years ago for 4th grade and it would have been painful for him if that course ended up only covering review rather than gave him an actual taste of both Algebra and Geometry (as well as Trigonometry). He is an outlier but DD11 not so much (as regards math at least) and for her it would still have been too much painful review as even her current Pre-Algebra course still moves too slowly. That is true for the better "GT" students at her school. Having said all that, it may well be that non-GT students would benefit from the old-fashioned approach but I don't have the education background to determine that.
Regarding Kumon, I am not sure that their curriculum is adequate. DS has a classmate who is doing Pre-calculus with Kumon but it always looks like Algebra to him. For example, one of the times that she asked DS' help with her Kumon Pre-calculus homework, it just required factoring quadratics, a skill that DS covered in his Algebra I course.
