This work describes the design and testing of a low-cost light-emitting diode (LED)-based nephelometer for turbidity analysis. It also describes the use of this nephelometer for context-based learning (CBL) experiments designed for teaching laboratories. The LED nephelometer is simple, low-cost, and robust, providing similar results as a…

In this article, simple models of optical computing circuits (1 x 4 demultiplexer (DEMUX), 4 x 1 multiplexer (MUX), Boolean logic, and half-adder (HA)) are shown with mechanically controlled plane mirrors. Photographs of the proposed computational circuits are also shown. It is very useful for the school student to understand optical logic and…

This article introduces a science game which can be used for innovative teaching and as an assessment tool. The Shadow Races Game is designed for first and second grade students to learn the phenomenon of shadow through inquiry-based activities and questions that require the children to apply inferences from those activities. In this amusing board…