Terra Nova Tests are norm-referenced achievement tests that measure basic concepts and skills commonly taught in schools throughout the country. Terra Nova is not a proficiency test such as the public school administers; proficiency tests are those in which students have been taught all the content and are now being tested on whether or not they “got” it.  This test is, therefore, not designed as a precise measure of any given curriculum or single instructional program. Terra Nova includes content students may not have been specifically taught, but that they could be expected to have mastered according to their cognitive ability.  
  
Results from tests provide information that compares students' achievement with that of a representative national sample.  This gives teachers the opportunity to compare their students with other students.  So, when a teacher says that a student scored at the 82nd percentile, that student's score was better than 81 percent of the scores of all the students who took the same norm-referenced test.