Student-teacher ratio

This shows the number of students per full-time equivalent (FTE) teacher. A low student-teacher ratio is not the same as a small class size. Some schools have teachers who teach specialized subjects with smaller classes. Other schools hire extra teachers to free up class preparation time for their core teaching staff. Both of these possibilities lower the overall student-teacher ratio but not the average class size.
Note that student-teacher ratios based upon FTE teachers can be exceedingly high for schools that have a large number of part-time teachers. If, for example, a small school has four part-time teachers at 25%, the student-teacher ratio at this school would be calculated based upon one teacher instead of four (because four teachers at 25% is equal to one full-time teacher). This in turn will make the student-teacher ratio appear higher than it really is. If your school has an exceptionally high student-teacher ratio, check with your school principal for an explanation.

Fonte: National Center for Education Statistics (EUA)

Student/Teacher Ratio

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This indicator does not take into account the quality of teaching or teacher qualifications. It also does not account for the curricula that are taught to our children. The indicator includes classes that have different types of teachers, such as special education and counseling, which are more prevalent in some schools. A better indicator would account for these differences and represent typical general education class sizes.

Data Source: NJ Department of Education