This study uses two different approaches to examining student outcomes and understanding in the context of aspects of acid-base chemistry. It introduces the use of evidence centered assessment design as a design framework of a multi-dimensional acid-base titration laboratory and as an analysis tool of student performances in a lab setting and in…

Science and engineering practices (SEPs) and crosscutting concepts (CCs) constitute a significant part of "A Framework for K-12 Science Education" (NRC 2012). As teachers, the role of the authors is to highlight the pivotal role that both scientific knowledge and the practices used to generate knowledge play in learning. This article…

Nitrate is a crucial parameter for assessing water quality, owing to its dual function in ecological systems. These functions can be beneficial or detrimental depending on whether nitrate concentrations are low or high, respectively. The ultraviolet spectrophotometric method (standard as 4500-NO[subscript 3]--B) is a classic method for determining…

Over the past 20 years research on reform efforts aimed at the chemistry laboratory has focused on different aspects of students' experiences including increasing content knowledge, improving student attitudes toward chemistry, incorporating inquiry activities, and providing students a hands-on experience related to the chemistry concepts learned…

Contribution: There are many on-line resources available to learn about optics and photonics, but no assessment tools exist to evaluate the learning achievements. This paper presents an assessment framework whose validity has been proven on a course with over 70 engineering students. Background: There is evidence that on-line resources complement…

Tomlinson's explanation of Artful Teaching and her 2017 expansion of this concept The Five Key Elements of Differentiation provide the theoretical framework of this examination of the need for science investigations in elementary schools. The Artful Teaching framework uses an equilateral triangle with vertices labeled The Teacher, The Student, and…

This paper presents an analysis of the scientific reasoning of a dyad of secondary school students about the phenomenon of dissolution of gases in water as they work on this in a simulated laboratory experiment. A web-based virtual laboratory was developed to provide learners with the opportunity to examine the influence of physical factors on gas…

The physical science curriculum design at Georgia Gwinnett College requires a theme-based course (lecture and group work, and laboratory) for nonscience majors. Increased student engagement is anticipated when science topics are taught in the context of a topic of which students can select during course registration. This paper presents the course…

We propose a simple and fascinating experiment for studying diffusion in gels using a pH-sensitive dye. By doping agar with methyl red, we obtain a gel which rapidly reacts to changes in pH by changing its absorption spectrum. The pH gradients can be followed using a digital camera, and we demonstrate here that the pH-sensitive colour changes can…

Many studies invoke moment of inertia (I[subscript ii]) as necessary and sufficient information to perceive cylinder length via wielding, yet some assert that I[subscript ii] is neither necessary (weight, "m", or static moment, M, are sufficient) nor sufficient for length judgments ("m" or M is necessary). Mathematical expressions for I[subscript…

A pencil lead successfully served as an electrode for the determination of ascorbic acid in commercial orange juice. Cyclic voltammetry was used as an electrochemical probe to measure the current produced from the oxidation of ascorbic acid with a variety of electrodes. The data demonstrate that the less expensive pencil lead electrode gives…

A recent article by Morse described interesting electrostatics experiments using an MBL charge sensor. In this application, the charge sensor has a large capacitance compared to the charged test object, so nearly all charges can be transferred to the sensor capacitor from the capacitor to be measured. However, the typical capacitance of commercial…

The effect of density inversion on the convective flow of water in a spherical glass flask cooled with the help of an ice-water bath is shown. The experiment was carried out by temperature measurements (cooling curves) taken at three different heights along the vertical diameter of the flask. Flows inside the flask are visualized by seeding the…

In this experiment, physical science students measured the mass of several soda cans, measured the mass and volume of water displaced when these cans were placed in water, and determined whether these cans sank or floated in water. Then, the students plotted graphs of the mass of displaced water versus the volume of displaced water, the mass of…

A wind energy focused curriculum for grades 4-8 was designed and implemented to promote the understanding of wind energy concepts with American Indian students. 57 students who participated in the 2009 summer program of the "Reach for the Sky" (RFTS) Science, Technology, Engineering, and Mathematics (STEM) received the curriculum. The…