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Although traditional lectures are still the dominant form of undergraduate instruction, there have been relatively few studies comparing various learner-centered and active learning teaching strategies to one another in order to guide professors in making informed instructional decisions. To study the impact of different active learning approaches, pre-test to posttest learning gains for students receiving instruction on introductory astronomy solar system topics through a combination of collaborative learning activities and formative assessment-driven activities were compared to the gains of students being taught the same topics by traditional lectures only. After traditional lectures, students improved from a pre-test score of 42% (n = 144) to 49% (n = 49). After lecture tutorials and classroom voting response systems improvement was to 73% (n = 72) Using a multiple-group comparison approach, similar earning gains were also observed when using visual-assessment and tutorial activities. Moreover, data from a Likert-style attitude survey of 264 undergraduates showed that, although they did not report a clear preference for one instructional mode over the other, the majority of students believed that the active and collaborative nature of the activities helped them learn. The results of this study add weight to the notion that most modern pedagogies are superior to traditional lecture, and that although the relative impacts of particular pedagogies are mostly indistinguishable from one another, they are all are better than traditional lecture alone.

A primary goal of general education introductory astronomy courses often is to provide students with examples of how science is actually done. Low to nonexistent mathematical prerequisites in some courses can make useful exercises difficult to find, and sometimes very difficult for students, especially if the exercises feature quantitative components. What follows describes an attempt to meet this goal through the use of actual exoplanet data, available online, from the NASA Kepler Mission. The exercise described guides the students through an aspect of scientific investigation that they may otherwise not experience, the handling and analysis of a large set of actual scientific data.

What follows is a description of the procedure for a directed-study in which a student, guided by a faculty member, attempted to identify potentially habitable exoplanets using actual data available online from NASA's "Kepler" Mission.

While teaching his first-ever introductory college astronomy course, I heard a graduate student make the comment that compared to other areas of astronomy, studying the solar system is just "stamp collecting." Coverage of the solar system in an introductory college astronomy course certainly "could" consist mostly of showing images and reporting facts, but by "using" observations that can be made from images and also data and other known facts about the objects, instruction on solar system topics can be more conceptual, involving just as much inquiry and discovery as any area of astronomy or physics.

What follows is a description of the procedure for and results of a simple experiment on the formation of impact craters designed for the laboratory portions of lower mathematical-level general education science courses such as conceptual physics or descriptive astronomy. The experiment provides necessary experience with data collection and analysis as well as practice with quantitative skills such as measurement and calculation in a manner that does not exceed the mathematical scope of the courses while, due to its hands-on nature and interesting topic, remaining engaging.

Throughout a general education course on sound and light aimed at music and art students, analogies between subjective perceptions of objective properties of sound and light waves are a recurring theme. Demonstrating that the pitch and loudness of musical sounds are related to the frequency and intensity of a sound wave is simple and students are easily able to draw the analogies with the color and brightness of light. When considering an entire spectrum, the presence of multiple frequencies and wavelengths of different intensities is perceived by the ear as sound quality, or musical timbre, while the perception of the eye is the tone or hue of a color. What follows is a description of a demonstration that draws the analogy between musical sound quality and the tone or hue of light in which the emission spectrum of hydrogen is considered and actually played as a musical chord.

Most combinations of musical tones are perceived as either "consonant," "pleasing" to the human ear, or "dissonant," which is "not pleasing." Despite being largely subjective in nature, sensations of consonance and dissonance can be quantified and then compared to the judgments of human subjects. The following is a description of several simple studies that can be carried out in the classroom of a physics of music or science of sound course.

What follows is a description of a theoretical model designed to calculate the playing frequencies of the musical pitches produced by a trombone. The model is based on quantitative treatments that demonstrate the effects of the flaring bell and cup-shaped mouthpiece sections on these frequencies and can be used to calculate frequencies that compare well to both the desired frequencies of the musical pitches and those actually played on a real trombone.

The effects of the mouthpiece and bell on the frequencies of the vibrating air column in a trombone can be demonstrated quite readily by first calculating the expected resonant frequencies of a piece of PVC pipe that is the same length as a trombone, then replacing portions of the PVC pipe of the same length with first a cup-shaped mouthpiece and then a flaring-bell section of a trombone. The trombone components used were from a new pBone plastic trombone that is not only much less expensive than a regular instrument, which is made mostly of brass, but also features components that are much lighter than those of a conventional brass trombone and is therefore easier to work with.

What follows is a description of a demonstration of superposition of waves and Fourier analysis using a set of four tuning forks mounted on resonance boxes and oscilloscope software to create, capture and analyze the waveforms and Fourier spectra of musical intervals.

An investigation of the possibility of life in the universe, or astrobiology, is an ideal topic for an interdisciplinary seminar course. Answering the topic's inherent questions--whether life exists elsewhere in the universe and, if it does indeed exist, whether we on Earth could contact such life--requires an interdisciplinary approach and multiple perspectives from the sciences, social sciences, and humanities. Described are several highlights of a community college's 15-week seminar course, Life in the Universe, including students' perceptions of the course elements as ascertained from an end-of-course survey. (Contains 4 tables.)

The "Life in the Universe Survey" is a twelve-question assessment instrument. Largely based on the factors of the Drake equation, it is designed to survey students' initial estimates of its factors and to gauge how estimates change with instruction. The survey was used in sections of a seminar course focusing specifically on life in the universe where it was designed and validated as well as in sections of introductory astronomy where life in the universe is only a single topic covered at the end of the semester. (Contains 10 figures and 1 note.)

What follows are several investigations involving string musical instruments developed for and used in a "Science of Sound & Light" course. The experiments make use of a guitar, orchestral string instruments and data collection and graphing software. They are designed to provide students with concrete examples of how mathematical formulae, when used in physics, represent reality that can actually be observed, in this case, the operation of string musical instruments. (Contains 2 tables and 8 figures.)

Misconceptions that students bring with them to the introductory science classroom plague every area of science and are especially prevalent in astronomy. One way to identify and possibly dispel some of these misconceptions is through the use of a misconceptions survey. The following is a report on the development, implementation, and some early results of the use of an Astronomical Misconceptions Survey. The survey was developed on the basis of previous research on common misconceptions in astronomy and used in sections of introductory college astronomy to identify which misconceptions were more and less prevalent among students and how effectively some of the misconceptions could be dispelled by various teaching methods. (Contains 3 tables and 6 figures.)

What follows is a description of several activities involving the Stefan-Boltzmann radiation law that can provide laboratory experience beyond what is normally found in traditional introductory thermodynamics experiments on thermal expansion, specific heat, and heats of transformation. The activities also provide more extensive coverage of and hands-on experience with the radiation law than is normally found in a traditional thermodynamics curriculum.

The beginning of a typical solar system "unit" in a traditional introductory astronomy course often consists of an overview of the different object types--planets, moons, and debris (asteroids, comets, and meteors), and now also Pluto's home, the Kuiper belt--prior to coverage of formation and more detail about the various object types. An important distinction that needs to be made prior to coverage of solar system formation or discussions of individual planets is between the two planet types: the Earth-like or "terrestrial" planets, and the Jupiter-like or "Jovian" planets. The following is a description of an activity designed to establish these categories through conclusions drawn by students after a guided analysis of planetary data.

The idea of sending students and the general public on a walk through a scale model of the solar system in an attempt to instill an appreciation of the relative scales of the sizes of the objects compared to the immense distances between them is certainly not new. A good number of such models exist, including one on the National Mall in Washington, D.C., starting at the Smithsonian Air and Space museum. A pioneering model and inspiration for our own is on the campus of the University of Colorado in Boulder, and there are others. Those at science museums are often used by the general public and field-trip groups, while the ones on college campuses are also used by students of introductory astronomy.

In recent years, short question-and-answer activities known as lecture tutorials that are designed to help students work with and discover concepts for themselves, rather than simply being told about them (lectured to) have become a popular tool for learner-centred teaching of introductory college astronomy. Students on such a course are usually non-science majors fulfilling a general education requirement and have a limited background in mathematics. The following is a description of the development, use and assessment of a lecture tutorial. (Contains 2 figures, 1 footnote, and 3 tables.)

Visual assessments and tutorials are instruments that rely on student construction and/or examination of pictures and/or diagrams rather than multiple choice and/or short answer questions. Being a very visual subject, astronomy lends itself to assessments and tutorials of this type. What follows is a report on the results of the use of visual assessments and tutorials for instruction on two specific solar system topics in introductory astronomy: the orbits of comets and extrasolar planets. (Contains 2 notes, 4 tables and 8 figures.)

The different combinations involved in additive and subtractive colour mixing can often be difficult for students to remember. Using transmission graphs for filters of the primary colours and a numerical scheme to write out the relationships are good exercises in analytical thinking that can help students recall the combinations rather than just attempting to memorize them. (Contains 1 footnote, 2 tables, and 4 figures.)

Consonance and dissonance are subjective perceptions that are reactions of the human ear to whether or not musical intervals sound "pleasing." The physical causes of consonance and dissonance are not as well understood as other subjective properties of sound perceived by the ear such as pitch, loudness, and quality (timbre). What follows is an overview of some attempts to quantify these sensations, and a new study with results that can be compared to several "dissonance metrics". (Contains 1 footnote, 5 tables, and 5 figures.)

The Star Properties Concept Inventory (SPCI) is among the first instruments made available to assess student gains in a major section or "unit" of a traditional introductory astronomy course, in this case the unit on stars. This is in contrast to instruments for an entire course, such as the Astronomy Diagnostic Test or the Lunar Phases Concept Inventory that is for a single subject. One of the intended uses of the SPCI is for comparison of the effectiveness of different instructional methods. The following is a report on the results of a study in which the SPCI was used as a pretest and post test to compare gains in active and collaborative student-centered instruction using lecture tutorials to those in traditional instructor-centered instruction. (Contains 5 notes and 2 figures.)

Use of a microphone attached to a computer to capture musical sounds and software to display their waveforms and harmonic spectra has become somewhat commonplace. A recent article in "The Physics Teacher" aptly demonstrated the use of MacScope in just such a manner as a way to teach Fourier analysis. A logical continuation of this project is to use MacScope not just to analyze the Fourier composition of musical tones but also musical intervals.

Simple experiments involving musical instruments of the woodwind family can be used to demonstrate the basic physics of vibrating air columns in resonance tubes using nothing more than straightforward measurements and data collection hardware and software. More involved experimentation with the same equipment can provide insight into the effects of holes in the tubing and other factors that make simple tubes useful as musical instruments. (Contains 4 tables, 6 figures, and 7 footnotes.)

In this exercise the US Standard Atmosphere is used as "data" that a student is asked to model by deriving equations to reproduce it with the help of spreadsheet and graphing software. The exercise can be used as a laboratory or an independent study for a student of introductory physics to provide an introduction to scientific research methods that may not otherwise be available from traditional classroom instruction.

The results of administering the Astronomy Diagnostic Test (ADT) to introductory astronomy students at Henry Ford Community College over three years have shown gains comparable with national averages. Results have also accurately corresponded to course goals, showing greater gains in topics covered in more detail, and lower gains in topics covered in less detail. Also evident in the results were topics for which improvement of instruction is needed. These factors and the ease with which the ADT can be administered constitute evidence of the usefulness of the ADT as an assessment instrument for introductory astronomy. (Contains 2 figures.)

In a recent "AstroNote," I described a simple exercise on the mass-luminosity relation for main sequence stars as an example of exposing students in a general education science course of lower mathematical level to the use of quantitative skills such as collecting and analyzing data. Here I present another attempt at a meaningful experience for such students that again involves both the gathering and analysis of numerical data and comparison with accepted result, this time on the relationship of the mass and lifetimes of main sequence stars. This experiment can stand alone or be used as an extension of the previous mass-luminosity relationship experiment.

What follows is an alternative to the standard tuning fork and quarter-wave tube speed of sound experiment. Rather than adjusting the water level in a glass or plastic tube to vary the length of an air column, a set of resonance tubes of different lengths is used. The experiment still demonstrates the principles of standing waves in air columns and can also be used to study end-correction as well as determining the speed of sound in air. (Contains 1 table and 3 figures.)

Comparing the predicted and actual rolls of combinations of both two and three dice can help to introduce many of the basic concepts of statistical thermodynamics, including multiplicity, probability, microstates, and macrostates, and demonstrate that entropy is indeed a measure of randomness, that disordered states (those of higher entropy) are more likely than more ordered ones. It can also show that predictions based on statistics are more accurate with larger samples of data. What follows is a simple experiment introducing some of the basic elements of statistical thermodynamics that can be a light and even fun way to end a unit on thermodynamics, often the end of a challenging first semester of introductory physics.

What follows is a description of a simple experiment developed in a non-mathematical general education science course on sound and light for fine arts students in which a guitar is used with data collection hardware and software to verify the properties of standing waves on a string.

In a previous article in this journal, we reported on a laboratory activity in which students used a derivation from the Stefan-Boltzmann law to calculate planetary temperatures and compare them to measured values from various (mostly online) sources. The calculated temperatures matched observed values very well with the exceptions of Venus and the dwarf planet Pluto. (Contains 1 table and 2 figures.)