An understanding of fractions is foundational to proportional reasoning and algebra. For example, a direct-variation relationship may include a constant of proportionality that is rational, and linear equations may have solutions that are fractions. Beyond that, a grasp of the concept of proportionality and of rational numbers is necessary for…

How does understanding the decimal system change with age and experience? Second, third, sixth graders, and adults (Experiment 1: N = 96, mean ages = 7.9, 9.23, 12.06, and 19.96 years, respectively) made number line estimates across 3 scales (0-1,000, 0-10,000, and 0-100,000). Generation of linear estimates increased with age but decreased with…

This study builds on two lines of research that have so far developed largely separately: the use of additive methods to solve proportional word problems and the use of proportional methods to solve additive word problems. We investigated the development with age of both kinds of erroneous solution methods. We gave a test containing missing-value…

Dot enumeration (DE) and number comparison (NC) abilities are considered markers of core number competence. Differences in DE/NC reaction time (RT) signatures are thought to distinguish between typical and atypical number development. Whether a child's DE and NC signatures change or remain stable over time, relative to other developmental…

Teachers are using technological innovations--including interactive whiteboards--in pre-K-grade 3 classrooms across the country. An IWB is a wall-mounted, touch-sensitive flat screen. When connected to a computer (or another electronic device) and a projector, it displays enlarged instructional content (such as a math word problem, pictures or…

The purpose of this study was to examine the relative effectiveness of two different learning modes; namely, a computer animation self-directed learning approach and a paper version of the self-directed learning approach, to 5th-graders' number sense development. Two 5th-grade classes, 30 students each, were selected from a public elementary…

This research study examined the development of 43 preservice elementary school teachers' conceptual understanding of place value after participating in a research-based constructivist unit of instruction in place value. The preservice teachers were enrolled in one of three terms of an elementary mathematics methods course in a private midwestern…

Widespread concern has been expressed about the persistent low mathematics achievement of students in the US, particularly for students from low-income and minority backgrounds and students with disabilities. Instructional gaming technology, when designed and fictionalized well, has the potential to improve the motivation and mathematics…

This paper reports on an ethnographically based study of entry level supermarket work. The study, carried out in a large suburban supermarket in Auckland, New Zealand, focused on the literacy and numeracy practices of supermarket assistants, all who had English as an additional language. It found that skills such as oral communication, personal…

This new addition to Math Solutions "Supporting English Language Learners in Math Class series" offers a wealth of lessons and strategies for modifying grades 6-8 instruction. Section I presents an overview of teaching math to English learners: the research, the challenges, the linguistic demands of a math lesson, and specific strategies and…

The use of random numbers is pervasive in today's world. Random numbers have practical applications in such far-flung arenas as computer simulations, cryptography, gambling, the legal system, statistical sampling, and even the war on terrorism. Evaluating the randomness of extremely large samples is a complex, intricate process. However, the…

There has been much debate, in both the linguistics and the psycholinguistics literature, concerning numbers and the interpretation of number denoting determiners ("numerals"). Such debate concerns, in particular, the nature and distribution of upper-bounded ("exact") interpretations vs. lower-bounded ("at-least") construals. In the present paper…

The boundary between convergent and divergent series is systematically explored through sums of iterated logarithms.

The Stoltz-Cesaro Theorem, a discrete version of l'Hopital's rule, is applied to the summation of integer powers.

A. Lobb discovered an interesting generalization of Catalan's parenthesization problem, namely: Find the number L(n, m) of arrangements of n + m positive ones and n - m negative ones such that every partial sum is nonnegative, where 0 = m = n. This article uses Lobb's formula, L(n, m) = (2m + 1)/(n + m + 1) C(2n, n + m), where C is the usual…