I've been thinking a lot about this article that came out recently:
http://hechingerreport.org/memorizers-are-the-lowest-achievers-and-other-common-core-math-surprises/Its not so much been the contention that memorizing is less useful than conceptual understanding but the further step argued that
"Some school districts, such as San Francisco Unified, are trying to slow down the math experience, requiring that advanced students go deeper rather than faster. Students still reach calculus but the pathway to calculus consists of deep understanding rather than procedures and memorization. This is an important move. There is no harm in students being introduced to higher-level mathematics earlier, as long as the mathematics is enjoyable and ideas can be explored deeply. Third graders can be fascinated by the notion of infinity, or the fourth dimension, but they do not need a race through procedural presentations of mathematics."
What this means in practice is SFUSD is forcing everyone to delay algebra until 9th grade and detracking at the same time.
I think in general Boaler fails to connect whether students taking Algebra earlier are conceptually weaker than their ninth grade counterparts or prove that advanced students gain anything from lingering in pre-algebra beyond just asserting that it can be "deeper".
Thankfully this is not our district but I worry that the trend will spread.