Many students in U.S. schools have trouble understanding fractions and Algebra II, the one difficultly occurring at the end of elementary school, the other in high school. One reason is that schools generally focus on one aspect of mathematics--calculation--and often fail to address the second aspect--interpretation. Also responsible is the…

This article describes a mathematics lesson taught by a 5th grade teacher who engages her class in an in-depth examination of one student's incorrect solution to a problem. Because the teacher consistently asks her students to devise alternative calculation strategies and explain how those strategies work, the students have come to expect that…

The aim of this study is to describe and analyze students' levels of understanding of exponents within the context of procedural and conceptual learning via the conceptual change and prototypes' theory. The study was conducted with 202 secondary school students with the use of a questionnaire and semi-structured interviews. The results suggest…

An exercise to compute LLE data is presented to illustrate the problems that can arise when the isoactivity equilibrium condition is used in the LLE calculations. A much more efficient condition is obtained when isoactivity is combined with the common tangent line criterion, avoiding false solutions that correspond with very low values of the…

In the "Sydney Morning Herald" of 23 March 2005, Ross Gittins argued that the funding arrangements for private schools positively encourage parents to move their children from the state system. The then Federal Minister for Education, Dr Brendan Nelson, in a letter to the "Herald" of 25-27 March, responded by saying that 68% of…

In this paper we present new evidence on the impact of school characteristics on secondary student achievement using a rich dataset from rural Bangladesh. We deal with a potentially important selectivity issue in the South Asian context: the non-random sorting of children into madrasas (Islamic faith schools). We do so by employing a combination…

The purpose of this ITEMS module is to provide an introduction to Markov chain Monte Carlo (MCMC) estimation for item response models. A brief description of Bayesian inference is followed by an overview of the various facets of MCMC algorithms, including discussion of prior specification, sampling procedures, and methods for evaluating chain…

Consider test data, a specified set of dichotomous skills measured by the test, and an IRT cognitive diagnosis model (ICDM). Statistical estimation of the data set using the ICDM can provide examinee estimates of mastery for these skills, referred to generally as attributes. With such detailed information about each examinee, future instruction…

The goal of this paper is to demonstrate the infrastructural nature of many modern conceptual technologies. The focus of this paper is on conceptual tools associated with elementary types of data modeling. We intend to show a variety of ways in which these conceptual tools not only express thinking, but also mold and shape thinking. And those ways…

Examined elementary and junior high school students in grades 2, 5, and 7 to determine baseline data about student performance on mental computation. Reports performance levels, difficulties of different types of mental computation, and preferences for doing computations mentally, with calculators, or by hand for each grade level. (MDH)

Sequential probability ratio testing (PRT), which usually is applied in situations requiring a decision between two simple hypotheses or a single decision point, is extended to include situations involving k decision points and [(k + 1)-choose-2] sets of simultaneous, simple hypotheses, where k>1. The multiple-decision point or…

Three models have been proposed to account for the relationship between the principle of commutativity and the development of more economical addition strategies, which disregard addend order. In the first and second models, it has been proposed that either discovery or assumption of commutativity is a necessary condition for the invention of…

Indicates that the calculator as a tool has an assured place in science teaching and gives examples of its use. Evaluates 18 different calculator models. (GS)

Multinomial-response models are available that correspond implicitly to tests in which a total score is computed as the sum of polytomous item scores. For these models, joint and conditional estimation may be considered in much the same way as for the Rasch model for right-scored tests. As in the Rasch model, joint estimation is only attractive if…

A framework is presented for characterizing competence for cognitive tasks, with a detailed hypothesis about competence for counting by typical 5-year-old children. It is proposed that competence has three main components that are called conceptual, procedural, and utilizational competence. Conceptual competence, which is discussed in greatest…