The principle of relativity is of fundamental importance in practice when we are solving problems in physics since the axiom states that the result of any physical experiment is the same when performed with identical initial conditions relative to any inertial coordinate system. Hence, conceptual knowledge of coordinate systems is central in any…

A simple photometric device was built to measure the kinetics of the title reaction. The device consisted of a green light-emitting diode (centered at 520 nm), a sample vial, a photodiode, and an Arduino microcontroller board. These parts were mounted on a black poly(lactic acid) holder which was manufactured by utilizing three-dimensional…

In this work, we present an experimental approximation to the study of the phenomenon of radioactivity in secondary schools, taking as an analogy the process of release of carbon dioxide in a carbonated beverage. In this way, we intend to facilitate the approach to the mathematical formalism and to the graphical description of this phenomenon, as…

High school students' difficulties with quantum physics (QP) are partly due to their limited understanding of the nature of science (NOS). The essence of QP can only be understood with informed views about NOS aspects such as the role of models and the relevance of controversies between physicists. Inversely, QP is an ideal topic for teaching…

In the transition from classical to modern physics, the idea of taking some certain quantities as distinct or bounded values and keeping the rest continuous has proved useful in dealing with many problems. In this paper we assume an upper bound on the velocity of classical particles and indicate that applying this assumption to electromagnetism…

The vertical bounce of a plastic egg was investigated by dropping the egg on a horizontal surface and filming the result with a video camera. If the egg is dropped on one end then it bounces just like a spherical ball. If the top end of the egg is pointing forwards or backwards when it lands on the surface, or if the egg is spinning when it lands,…

There are three aspects of science: (1) scientific knowledge: what we know about the natural world, which would include crosscutting concepts; (2) scientific practices: skills and knowledge necessary for building scientific knowledge; and (3) nature of science (NOS): how science works (Bell et al. 2003). Most science instruction emphasizes the…

Conrad Hal Waddington (1905--1975) was an English biologist who was especially interested in the big (metaphysical) questions of life. His thinking has become part of the foundation of modern systems biology. This article applies his thinking to middle-years school biology curricula (for ages 11-16), to see if their approach to epistemic questions…

Over the past several decades it has become increasingly important to understand nature of science (NOS) for scientific literacy in science education. Science education researchers have suggested using socio-scientific issues to create a context for that purpose. The present fast-moving coronavirus or COVID-19 pandemic as a socio-scientific issue…

There is, broadly speaking, an agreement within the international science education community that comprehension of the nature of science (NOS) should be a key element in the scientific literacy of citizens. During the last few decades, several didactic approaches have emerged concerning what and how to teach NOS. Also, one of the basic objectives…

The private company SpaceX regularly launches satellites into geostationary orbits. SpaceX posts videos of these flights with telemetry data displaying the time from launch, altitude, and rocket speed in real time. In this paper this telemetry information is used to determine the velocity boost of the rocket as it leaves its circular parking orbit…

A versatile experiment is described for the high school and college laboratory setting based on the synthesis of biobased polymers prepared from inexpensive, renewable, and nonhazardous chemicals. Combinations of readily available citric acid, glycerol, and tapioca root starch are used to prepare three polymeric materials with different observable…

As a high school AP Physics 1 and 2 teacher, Sean Crumley wanted to create a curricular unit that would authentically connect literacy, opportunities for writing, and science standards while engaging a 21st-century student. This article provides an example of how Crumley incorporated writing into one of his AP physics units, and it could serve as…

A safe, convenient, and environmentally benign laboratory experiment for the synthesis of biodiesel from six kinds of vegetable oils has been developed for the introductory organic chemistry laboratory. The experiment uses ultrasonic irradiation in the presence of a base catalyst at room temperature and atmospheric pressure. Because of safer and…

For more than 10 years, I had taught Kepler's laws and the law of universal gravity without a corresponding experiment. I sometimes remember how these topics were difficult for me in my high school days to understand. At that time, I thought that one of the reasons for my difficulty was that these phenomena cannot be visualized using physical…