What is the most desirable percentage of the class that should easily answer items on a norm-reference test?

In the context of norm-referenced testing, the most desirable percentage of the class that should easily answer items is typically 50% or less. This benchmark allows for a clear distinction between various levels of student understanding and performance.

When only about half of the students can answer an item correctly, it indicates that the test is effectively challenging and discriminative, enabling educators to identify students who are below, at, or above average performance. This differentiation is crucial for tailoring instruction to meet the needs of diverse learners.

Setting the threshold at around 50% helps ensure that the items are neither too easy nor too difficult, thus maintaining a balance in assessing knowledge without skewing the results due to over-simplified content. If the pass rate were significantly higher, it could suggest that the test is not adequately measuring the intended learning objectives.