Translating words into equations: a cognitive load theory approach

The conditions under which explicit instruction in checking, combined with worked examples, may be beneficial in learning how to translate sentences into algebraic equations was examined from the perspective of cognitive load theory. In two experiments it was shown that Grade 8 and 9 students were initially disadvantaged by the inclusion of a checking method. However, after a more substantial period of acquisition, students with a low level of mathematical knowledge performed significantly better after receiving checking instructions than those who did not receive checking instructions. In contrast, higher knowledge students were continually disadvantaged by the inclusion of a checking method. The positive effect of checking for lower knowledge students and the negative effect for higher knowledge students in this domain is a further example of the expertise reversal effect.     

A Study of Two Instructional Sequences Informed by Alternative Learning Progressions in Genetics

Learning progressions (LPs) are hypothetical models of how learning in a domain develops over time with appropriate instruction. In the domain of genetics, there are two independently developed alternative LPs. The main difference between the two progressions hinges on their assumptions regarding the accessibility of classical (Mendelian) versus molecular genetics and the order in which they should be taught. In order to determine the relative difficulty of the different genetic ideas included in the two progressions, and to test which one is a better fit with students’ actual learning, we developed two modules in classical and molecular genetics and alternated their sequence in an implementation study with 11th grade students studying biology. We developed a set of 56 ordered multiple-choice items that collectively assessed both molecular and classical genetic ideas. We found significant gains in students’ learning in both molecular and classical genetics, with the largest gain relating to understanding the informational content of genes and the smallest gain in understanding modes of inheritance. Using multidimensional item response modeling, we found no statistically significant differences between the two instructional sequences. However, there was a trend of slightly higher gains for the molecular-first sequence for all genetic ideas.     

The significance of context for curriculum development in engineering education: a case study across three African countries

Curriculum reform is a key topic in the engineering education literature, but much of this discussion proceeds with little engagement with the impact of the local context in which the programme resides. This article thus seeks to understand the influence of local contextual dynamics on curriculum reform in engineering education. The empirical study is a comparative analysis of the context for curriculum reform in three different chemical engineering departments on the African continent, located in Kenya, Tanzania and South Africa. All three departments are currently engaged in processes of curriculum reform, but the analysis shows how the different contexts in which these efforts are taking place exert strong shaping effects on the processes and outcomes for that reform.     

Family poverty, welfare reform, and child development

Our review of research suggests that family poverty has selective effects on child development. Most important for policy are indications that deep or persistent poverty early in childhood affects adversely the ability and achievement of children. Although the 1996 welfare reforms have spurred many welfare-to-work transitions, their time limits and, especially, sanctions are likely to deepen poverty among some families. We suggest ways policies might be aimed at preventing either economic deprivation itself or its effects.     

The pension subsidy of educational inequality

Public school teachers receive on retirement a pension typically equaling 75% of the average salary earned during the three peak years. While the teachers pay part of the costs of their defined benefit pension through payroll deductions, most of the cost is subsidized by the state. The pension subsidy, a far from neglible component of the per pupil cost of instruction, is particularly high in those school districts that pay high salaries and enjoy low student/teacher ratios. It is a regressive subsidy highly correlated with school district income and wealth. Several alternative reform measures are considered.     

Books: An Essential Part of Essential Libraries

As public libraries strive to remain essential parts of their communities in tough economic times, the centrality of books to the library's mission is explored.