The Landau-Zener formula provides the probability of non-adiabatic transitions occurring when two energy levels are swept through an avoided crossing. The formula is derived here in a simple calculation that emphasizes the physics responsible for non-adiabatic population transfer. (Contains 2 figures.)

In the western half of the United States, fire bombers are not an uncommon sight. During the "fire season," which can extend from June through November, these specially modified aircraft are used to drop fire retardant chemicals or water on wildfires. It can be an entertaining and instructive classroom exercise to use pictures of these…

Connecting mathematical thinking to the natural world can be as simple as looking up to the sky. Volunteer bird watchers around the world help scientists gather data about bird populations. Counting flying birds might inspire new estimation methods, such as counting the number of birds per unit of time and then timing the whole flock's flight. In…

The persistently low college attainment rates of youth from poor families are partly attributable to their uncertainty about college affordability. The current federal financial aid system does not provide specific information about college costs until just before college enrollment and the information is only available to students completing a…

The present study examined whether multiple opportunities to learn math were associated with smaller socioeconomic status (SES) disparities in fifth-grade math achievement using data from the NICHD Study of Early Child Care and Youth Development (SECCYD; N = 1,364). High amounts of procedural math instruction were associated with higher…

How to compute and report subscores for a test that was originally designed for reporting scores on a unidimensional scale has been a topic of interest in recent years. In the research reported here, we describe an application of multidimensional item response theory to identify a subscore structure in a test designed for reporting results using a…

Enabling learning through meaningful classroom experiences has always been a challenge for teachers. Bringing about a balance of the "conceptual" and the "hands-on", along with contextual embeddedness in problem-solving situations, broadly characterises the experience of development and trials of three Design and Technology…

The purpose of this study was to determine the efficacy of specific, individualized training for students with different levels of mathematical difficulties. Fifty-four students, with either severe or mild math difficulties, were assigned to individualized training or to a control condition. Ten students with severe math difficulties…

Scratch, a visual programming language, was used in many studies in computer science education. Most of them reported positive results by integrating Scratch into K-12 computer courses. However, the object-oriented concept, one of the important computational thinking skills, is not represented well in Scratch. Alice, another visual programming…

Background: Insufficient physical activity among urban youth increases risk of chronic disease.Purpose:This study assessed reported physical activity to determine when disparities in participation emerge and what ecologically guided factors are linked with high activity. Methods:We administered a cross-sectional survey to a diverse sample of 321…

Mastering single-digit arithmetic during school years is commonly thought to depend upon an increasing reliance on verbally memorized facts. An alternative model, however, posits that fluency in single-digit arithmetic might also be achieved via the increasing use of efficient calculation procedures. To test between these hypotheses, we used a…

This study explored the nature of mathematics anxiety in a sample of 106 ethnically and linguistically diverse first-grade students. Although much is known about mathematics anxiety in older children and adults, little is known about when mathematics anxiety first emerges or its characteristics in young children. Results from exploratory factor…

The results of an exploratory study into measurement of elementary mathematics ability are presented. The focus is on the abilities involved in solving standard computation problems on the one hand and problems presented in a realistic context on the other. The objectives were to assess to what extent these abilities are shared or distinct, and…

In a 9-month training experiment, 64 first graders with a risk factor were randomly assigned to computer-assisted structured discovery of the add-1 rule (e.g., the sum of 7 + 1 is the number after "seven" when we count), unstructured discovery learning of this regularity, or an active-control group. Planned contrasts revealed that the…

This article reports the findings from a comparative analysis that examined several mathematical content strands, reasoning processes, and emphasis on technology in prior K-8 state mathematics standards and the Common Core State Standards for Mathematics (CCSSM). Various methodological tools were utilized to compare and contrast CCSSM with prior…