The phrase "a sample of schools" is correct and usable in written English.
It can be used when referring to a selection or subset of schools for research, analysis, or comparison purposes.
Example: "In our study, we collected data from a sample of schools to assess the effectiveness of the new curriculum."
Alternatives: "a selection of schools" or "a subset of schools".
The E.P.A. tested for radon in a sample of schools nationwide between 1990 and 1991.
A 2008 Ofsted report that looked at a sample of schools providing opportunities to learn outside the classroom found that, when implemented well, those opportunities "contributed significantly to raising standards and improving pupils' personal, social and emotional development".
The most popular higher education destinations for international school students are the U.S., U.K. and Canada, according to ISC Research based on a sample of schools.
The PISA sample was constructed by randomly selecting 50 students aged 15 years from each school from a sample of schools designed to represent all states and sectors.
Within a sample of schools where every pupil has a tablet computer, a quarter of secondary pupils described themselves as internet "addicts".
Estyn will now track the progress of a sample of schools over the next two years, reporting on the impact of the Welsh government's new literacy and numeracy framework.
The aim of this study was to investigate whether these cognitive benefits extended to a sample of school-aged children.
The Swedish government tried the new policy in a sample of school districts, selected to be representative of the country as a whole.
We surveyed a sample of school principals who served as "key informants" about the communities in which their schools were located.
The purpose of this paper was to investigate whether information about radiography careers that was placed on the Internet was accessible, accurate, understandable, comprehensive, abundant and attractive to a sample of school children.
They include 'diabetes', 'school', and 'camp', all of which clearly reflect that this was a sample of school aged young people attending a camp for children with diabetes.
