The problem with their piece is that the curriculum (AKA the specific content in courses) is only one of many issues. Their analysis is limited, and here's why.
There are numerous examples from the K-12 system, where schools have adopted a research-based, NSF funded curriculum like IMP or CPM. Many times these programs are shut down by some exogenous force. For example parents, who have good intentions in their hearts have organized and shut programs down. They say things like, "Well that's not how I learned it...," never mind that the world has changed and students are being prepared for new challenges, not challenges from the 19th century. Or a new superintendent wipes out the programs, or a new principal comes in and moves teachers to new classes or grade levels, or budget cuts,..., the list could go on and on. I note that none of these people do this intentionally. People in education and parents are well-intentioned. They mean well. It's just that we don't know better as a society, and look for simple fixes for long-term, multi-layered problems. Insufficient.
The problems we face now are complex, and my sense is that they are on the order of magnitude to problems related to ecosystem sustainability. Our educational system is vast and complex, with outdated doctrines interfacing with modern challenges, and a currently fashionable and misguided desire to apply business models to non-business systems. So when someone says, "Just fix X, and all will be good," I know that it just won't.
Content (i.e. textbooks or materials) is just one small slice of the education pie. In addition to content is
- Instruction (and all this huge category entails)
- Student attitudes, beliefs, habits of mind, experience with math, and their natural cognitive development mathematically. (Example: the developmentally appropriate order of topics is sometimes different than the logical order in a subject.)
- External issues to the classroom like tenure and promotion for research (but not teaching), pacing plans, poverty, etc.
- Systemic issues like standardized testing (K-12) or standardized courses (calculus)
- The factory model mindset held by most people regarding education. We value certain kinds of intelligence. Math and reading are at the top....Art, Dance, Music, craft, and manual skills are at the bottom, which leaves some students feeling marginalized for being born with the "wrong" abilities.
- We educate students in disciplines in ways such that they are not connected to each other, even though they often are connected and of more value when studied as a whole.
- Community and culture. Most people think math is "2+2 = 4." That there is only one answer. That there is only one way to get to that singleton answer. That math is immutable and the same across all time. Learning math means you know how to calculate. Additionally, Parents, even well educated ones, can destroy a positive change, thinking that they are doing a good thing. I do not doubt parents' love of their children or desire for good education. It's just that we as a society are generally naive about what math is. What we assume to be true about math is actually false. So based on false assumptions we act unwittingly against our own interests. Mathematicians bear some of this responsibility, as we are not good ambassadors of our wonderful subject.
So how does IBL come into play? At the college-level, a math instructor, who uses IBL, can control enough of the ecosystem within the classroom to construct a little, temporary greenhouse. This little greenhouse has enough of the conditions necessary to foster intellectual growth and provide opportunities for students to undertake the effort required for transformative changes. Considering how to scale these little greenhouses up is one way to realize the enormity of the challenge in education reform, and emphasizes that changing a textbook or the curriculum is like upgrading the rake or the shovel to a new, more effective one. While it's a necessary step in the right direction, it is insufficient.