The phrase "a subset of schools" is correct and usable in written English.
It can be used when referring to a specific group of schools that are part of a larger category or classification.
Example: "The study focused on a subset of schools that implemented innovative teaching methods."
Alternatives: "a group of schools" or "a selection of schools".
o Whenever feasible, solutions should be piloted in a subset of schools and classrooms and rolled out broadly only when the early results are promising.
Two main designs are considered: lot quality assurance sampling (LQAS) of children from all schools; and a geostatistical design that samples a subset of schools and uses semi-variogram analysis and spatial interpolation to predict prevalence in the remaining unsurveyed schools.
aPISA Quality Monitors observe the assessment in a subset of schools to verify that test administration and other procedures adhere to the international guidelines.
The secondary goal was comparing the effect of the two interventions with the control group on the presence of E. coli on pupils' hands in a subset of schools.
Multiple rounds of structured observations of hand washing events after latrine use were conducted in 60 Kenyan schools, and hand rinse samples were collected one time in a subset of schools.
Among institutions offering the traditional five year undergraduate programmes (traditional courses), we identified a subset of medical schools formed within the past decade ("new" schools; n=4) that have stated a different approach to student admissions.
While total enrollment has been declining steadily since the early 2000s in Christian graduate theological schools in the U.S. and Canada that are accredited through the Association of Theological Schools (a subset of theological schools for which historical data are readily available), we find chaplaincy programs proliferating.
It is possible to select a subset of grammar schools and to suggest that the minority of children from poorer backgrounds who attend that small set do go on to get better GCSE results, but that does not provide evidence that the grammar school model is good in general.
Preliminary findings in a subset of the schools suggested that the extra calories do make a difference: School districts that increased calories the most showed the most striking improvement in test scores, especially in mathematics.
Drexel is among a subset of major schools in the nation including Northeastern, the Rochester Institute of Technology, the University of Cincinnati and Kettering that offer highly sophisticated work-for-credit programs called "co-ops".
… There's a subset of charter schools that are not operating better options and need to be closed".
