This study aims to evaluate a differentiation approach that was recently developed to teach mathematics to gifted middle school students in terms of its practice by teachers by studying the effect of the approach on achievement among both gifted and non-gifted students. From mixed research methods, the study used an explanatory design. It was…

The concept of "implementation fidelity" is broadly used to capture the extent to which an intervention is executed as intended by the designers of the intervention (Century, Rudnick, & Freeman, 2010; Huntley, 2005, McNaught, Tarr, & Sears, 2010, Munter, 2010). Though implementation fidelity instruments are often used to assess…