I teach music. I have no expertise in the teaching of language arts or mathematics. So maybe someone will help me out with this question:

When I look at the Common Core math standards, I see bands for Kindergarten through Grade 8 -- but not for Grades 9 through 12.

The K-8 Standards are quite precise: Kindergarten, for example, needs to work with numbers 11-19 (I guess we just assume they come into school knowing 1-10...), Grade 1 goes up to 120, Grade 2 to 1000, and so on.

Again, I have enough experience and training as an educator to know I don't have a well-informed opinion as to whether that is developmentally appropriate (would that others had my humility). But let's assume this is a reasonable, evidenced-based sequence. Is it not based on an assumption that all Kindergarteners have the prerequisite education and capability to work with two-digit numbers?

Yet we know that that 5-year-olds have wildly varying readiness for school:

Access to high-quality preschool is particularly needed for low-income children of color, who often start kindergarten behind their peers. By school entry, the gap between the wealthiest children and the poorest children is already pronounced. Children from low-income families are a year or more behind their more advantaged peers. By age 4, low-income children have heard 30 million fewer words than children from more-affluent families and have vocabularies that are half as extensive. The gaps that start at an early age only grow larger, and catching up becomes ever more difficult. By the first grade, for example, there is a full one-year reading gap between English language learners and native English speakers—a gap that increases to a two-year gap by the fifth-grade.

Now, I'm all for high standards, and I don't think we should accept the premise that children who start out behind will inevitably remain behind. I think the way we're currently addressing the issue is stupid, pernicious, and an insult to the teaching profession... but in the spirit of the holiday, I'll put that aside and get back to my question:

The folks who embrace the world view exemplified by the Common Core seem to think it's absolutely essential that we set a "rigorous" standard for 5-year-olds, whether they are ready to meet that standard or not. Then they seem to think that standard should continue to be set each year -- regardless of whether students of varying backgrounds or skills can meet it -- all the way until Grade 8.

And then...

As if by magic, when students get to high school, the notion of a universal grade level standard thrown out the window!

Suddenly, it appears to be just fine that some freshmen take Algebra I, some take Geometry, and some take Algebra II. It seems acceptable that some upperclassmen head on a track toward calculus in high school, and some don't. Even the College Board seems OK with the idea that some calculus students should take harder (BC) calculus, and some should take an easier version (AB).

If differentiation in learning trajectories is OK at the high school level -- even within the Common Core standards -- why isn't it OK at the beginning of a child's education, when the differences in school readiness, ability, and development are so great?

This is a question that is so obvious to me that I can't believe no one has addressed it; therefore, I've convinced myself it must be dumb. Except my own experience and training tell me it's not. Young children are hugely different in their reading, mathematics, music, artistic, physical, and other skills. I see this every day; everyone who works in Pre-K-5 schools knows this. So why is it OK to differentiate instruction, testing, and accountability in high school, but not in the grades below?

The PARCC tests, which are aligned with the Common Core, actually have two different "pathways" for mathematics. I don't have a problem with that -- I'm only asking why we have decided 15 is the mystical age at which sorting in mathematics is warranted. Why not 13? Or 11? Or 5? Where is there any evidence that this is appropriate?

Where is there any evidence that holding the teachers of Grade 6 mathematics accountable for their students' results in a universal test is appropriate, but doing the same for Grade 10 teachers is not?

Someone help me out here. Please.

Jersey Jazzman ponders the Common Core (artist's conception).