[b]I'd like to present the Principal with research data showing that ability grouping, done correctly, helps ALL students.
In building this argument, I wouldn't worry about
all students, I'd worry about low achievers, because when the principal talks about "overall student achievement," that's Navajo code-talk for "state test scores." That's her concern, because that's the legislative mandate under which she operates. If you can show how heterogeneous grouping does not boost basic test scores, you've got an argument she'll take seriously.
Alternatively, if you can offer her a compromise where you both get what you want, that's something she might consider. For example, if the school offered my DD7 a 20-min pullout for math at her ability level (compacting FTW), and then asked her to play teacher's assistant during the regular math period in the heterogeneous classroom, that'd be something we'd be interested in trying. That's a situation that wouldn't suit all gifted kids, naturally, but it would fit mine.
