A student response system (SRS) with an engaging and interactive curriculum to support 21st -century skills could increase student performance in U.S. schools. This article will include student and teacher feedback to provide educators with possible solutions to poor student performance....

The "distance effect" measuring the elasticity of trade flows to distance has been rising since the early 1970s in a host of studies based on the gravity model, leading observers to call it the "distance puzzle". This paper reviews the evidence and explanations. Using an extensive data set of...