[lschueller]

Sounds good. The school systems are messed up, everybody agrees on that. But the article is missing out the underlying cause for the results. What exactly caused the beneficial outcome? Montessori itself is quite a vast term nowadays.

[fhsm]

The article is clear — lottery offer of a seat in a school which met inclusion criteria. Inclusion criteria are clearly outlined in the supplemental materials which are a single URL away which also include details on the allocation.

https://www.pnas.org/action/downloadSupplement?doi=10.1073%2...

Talk of causation anywhere other than the unit of randomization is speculation.

[scythe]

The definition is holistic:

>As shown in Figure S1, we began with a list of 588 public Montessori schools in the United States supplied by the National Center for Montessori in the Public Sector

>[procedural stuff, possibly introducing bias but not definitional]

>Finally, because “Montessori” is not a trademarked term, we checked whether schools met our minimum standards for Montessori inclusion

>- At least 66% of the lead Primary classroom teachers are trained by one of the two most prominent Montessori teacher training organizations, the Association Montessori Internationale (AMI) or the American Montessori Society (AMS). One school was excluded on this basis.

>- No more than two adults, the trained teacher and a non-teaching assistant, in the classroom on a regular basis. No school was excluded on this basis

>- Classrooms are mixed-age, with at least 18 children ranging from 3 to 6 years old. Five schools did not mix ages so were excluded.

>- At least a 2-hour uninterrupted free choice period every day. Five schools were excluded on this basis.

>- Each classroom has at least 80% of the complete set of roughly 150 Montessori Primary materials, and fewer than 5% of the materials available to children in the classroom are not Montessori materials. No school was excluded for failing to meet this criterion. [italics mine, furthermore, holy crap!]

I think one thing that is particularly noticeable is that, while there is definitely some particular form of education being put forward here which is interesting, there is obviously a very "aesthetic" trend as well, because plenty of schools are failing on the practices and the teachers while somehow none are failing the materials. But maybe this is actually just path-dependence in measuring the exclusion per criterion?

[novia]

the definition in your linked paper is quite self referential

[silisili]

The underlying cause is that only well to do parents choose Montessori. None of the pesky low income folks to throw off the test score.

[mcv]

These were randomised. It sounds like they eliminated this selection bias.

Also, this is just about preschool. For regular school, I've grown more skeptical, because it didn't work well for either of my kids. They struggled with the independence and planning, and didn't get much done. One switched to special education during primary school and is doing excellent there (but that has much more guidance and costs more, though I wish it was available for everybody), the other switched to a regular school during secondary school after almost failing to pass year after year despite his extraordinary intelligence. He's doing somewhat better now.

It's a good option to have, but it's quite likely the advantage is bigger for preschool than school.

[technothrasher]

I think it largely depends upon the child. I thrived in a Montessori environment right through sixth grade before transitioning to a standard “prep school” and found myself way ahead of the other kids in a lot of things.

  Alternately, my son was much the same as your kid.  He struggled in a Montessori school which was very similar to the one I went to (in fact, my lower elementary teacher was the learning specialist at his school while he was there).  He couldn’t handle the open structured style of the learning, and just floundered badly. We ended up getting him into a much more structured special ed school where he succeeded and is now off doing well at college.

[mcv]

It absolutely depends on the child. I phrased it too generally. I like the idea of Montessori a lot, but it depends a lot on executive skills: being able to plan, start project, finish projects, etc. My kids both sucked at that, and I'm not great at it either. My oldest son, despite his stellar IQ, completely drowned in projects. No idea what to do, when to start, how to start, how to finish it, and even when he finished it, he forgot to turn it in. He simply needs more guidance.

He's now finally getting better at it, at 16, which is about time, because at the university, you have to be able to do all of this. I sucked at it in university, so maybe it's actually good that he ran into these problems earlier than that, but for him to actually finish school, it was not a good fit.

[thaumasiotes]

> My oldest son, despite his stellar IQ, completely drowned in projects. No idea what to do, when to start, how to start, how to finish it, and even when he finished it, he forgot to turn it in. He simply needs more guidance.

> He's now finally getting better at it, at 16, which is about time, because at the university, you have to be able to do all of this.

You definitely don't.

[mcv]

Struggling with this is exactly why I never quite finished my degree. All the papers where I had to choose what to write about, without having an immediate topic I just had to write about, never even got started. Thesis is an even bigger project. Dropping out and not having to do it anymore felt like a relief.

[em-bee]

you may be comparing different countries. not needing to be able to do all of this sounds like a very school like university. the universities i know are not like that, and you most certainly need those skills.

[themaninthedark]

So while it is randomized in the terms of who they chose to participate, the students did attend already existing schools. This could lead to selection bias from the participates, as the schools themselves are located in wealthier areas as that is where their clientèle are.

Lower income families may not have been able to take advantage of the lottery due to distance constrains thus self-opting out.

I have not read the study methodology details, the schools may have been chosen to avoid this problem but just wanted to point out that just because something say "random lottery" it may not be.

[dmurray]

But the control group was families who did opt in and who lost the lottery.

[cma]

Still the ones who got in would be with more other students who opted in, the ones who didn't get in would be with more students who didn't opt-in to the lottery.

You would need to have a second group of those who lost the lottery and were all put into the same non-Montessori school with no others who didn't opt-in maybe.

[rahimnathwani]

Oh you mean it could all be peer group effects?