In our science for non-science majors course "21st Century Physics," we investigate modern "Hubble plots" (plots of velocity versus distance for deep space objects) in order to discuss the Big Bang, dark matter, and dark energy. There are two potential challenges that our students face when encountering these topics for the…

Cell water relationships are important topics to be included in cell biology courses. Differences exist in the control of water relationships in plant cells relative to control in animal cells. One important reason for these differences is that turgor pressure is a consideration in plant cells. Diffusion and osmosis are the underlying factors…

Identifies points where beliefs are important when making decisions about how graphs are drawn. Describes a simple case of the reaction between 'bicarb soda' and orange or lemon juice and discusses how drawing a graph becomes a statement of belief. (KHR)

Using movie scenes about being trapped in quicksand as a starting point, this inquiry-oriented lesson engages students in a novel study of density. Students collect and graph data collected on a variety of objects placed in a mixture of sand and water. From their findings, students consider misconceptions about quicksand and its real dangers. (DLH)

Presents an approach that combines the discovery method with graphing skills and allows students to uncover scientific laws on their own. Attempts to make the discovery method more quantitative while still teaching students how to think scientifically. (JRH)

Uses graphs to involve students in inquiry-based population investigations on the Wisconsin gray wolf. Requires students to predict future changes in the wolf population, carrying capacity, and deer population. (YDS)

Described is how the crumpling of paper balls exhibits the concept of a topological dimension similar to fractals. The mass of the crumpled paper ball is found to be proportional to its diameter raised to a nonintegral power. (KR)

Presents the "Before Technology and After Technology" lab where students first complete a simple lab and graph the data by hand and then repeat the lab using graphing calculators. Enables students to see how technology can make data collecting, graphing, and analyzing more fun. (JRH)

Presents an activity in which students draw the decay curve for a medical radioisotope and determine its half-life. (MKR)

A quantitative and inexpensive way to measure the rate of enzymatic reaction is provided. The effects of different pH levels on the reaction rate of an enzyme from yeast are investigated and the results graphed. Background information, a list of needed materials, directions for preparing solutions, procedure, and results and discussion are…

A procedure that allows students to view an entire bacterial growth curve during a two- to three-hour student laboratory period is described. Observations of the lag phase, logarithmic phase, maximum stationary phase, and phase of decline are possible. A nonpathogenic, marine bacterium is used in the investigation. (KR)

Described is a situation where students are allowed to enlist the aid of a computer graphing program to produce graphs for their lab reports. (KR)

Presents a simple qualitative system for sketching all manner of acid-base titration curves, requiring only the approximate values of the acid or base ionization constants. (WRM)

Describes the construction of a marshmallow catapult to investigate trajectory concepts. (MKR)

Presented is a way to measure the sun's radiation by using a radiometer. Directions for building both simple and complex radiometers, circuit diagrams, and an explanation on how they work are included. (KR)