We apply an advanced data visualization technique, "Sankey diagram," to explore how middle-school students (N = 343) solved problems in a game-based algebraic notation tool. The results indicate that there is a large variation in the types of students' strategies to solve the problems, with some approaches being more efficient than…

Although basing instruction on a learning trajectory (LT) is often recommended, there is little evidence regarding the premise of a LT approach--that to be maximally meaningful, engaging, and effective, instruction is best presented one LT level beyond a child's present level of thinking. This hypothesis was evaluated for an empirically-validated…

Measures of teacher mathematical knowledge are notoriously difficult to develop (e.g., Orrill et al., 2015). This is in part because of the multidimensional nature of teacher knowledge. As part of two separate projects being undertaken by this research team, we have attempted to write assessments of teacher pedagogical content knowledge (PCK) in…

Negative relationships between mathematics anxiety and achievement appear in many countries globally (Lee, 2009; OECD, 2013), suggesting that mathematics anxiety could be an underconsidered factor in regions with persistently low mathematics achievement. We draw on a national sample of students and their teachers in Belize to examine relations…

It has been shown in multiple studies that expert-created on-demand assistance, such as hint messages, improves student learning in online learning environments. However, there are also evident that certain types of assistance may be detrimental to student learning. In addition, creating and maintaining on-demand assistance are hard and…

When designing an instructional tool and using it in pedagogical activities, it is essential that designers and users understand what pedagogical affordances and constraints the tool provides to support its successful integration into targeted pedagogical activities. Toward this end, we developed "Pedagogical Affordance Analysis (PAA)."…

Many studies have shown that visual representations can enhance student understanding of STEM concepts. However, prior research suggests that visual representations alone are not necessarily effective across a broad range of students. To address this problem, we created a novel, scaffolded form of diagrammatic self-explanation in which students…

The concept of equivalence can be elusive to students and can be confounded with unproductive understandings of the equals sign. Using the game-based digital algebraic notation system, From Here to There! (FH2T), students explore ideas of equivalence by dynamically transforming expressions or equations among mathematically equivalent states. In…

This study examined if and how thinking time, defined as the time from the start of the problem to the students' first action to solve, influences their problem-solving efficiency, defined as the number of steps taken to solve the problem, using Graspable Math, a web-based mathematical tool. We found that: (1) students who took longer to think…

This study examined whether the efficacy of a 50 lesson mathematics intervention program focused on whole number concepts for at-risk kindergarten students, ROOTS, differed by group size and whether initial skill moderated intervention effects by group size. The study utilized a randomized block design with at-risk students (n = 1,251) within…

This study examined the cost effectiveness of a 50 lesson mathematics intervention program focused on whole number concepts for at-risk kindergarten students, ROOTS. The study utilized a randomized block design with 1,251 at-risk students within 138 classrooms randomly assigned to one of two active treatment conditions (small groups of either two…

We use a novel database of the preservice apprenticeships ("student teaching placements") of teachers in Washington State to investigate the relationship between mentor effectiveness (as measured by value added) and the future effectiveness of their mentees. We find a strong, positive relationship between the effectiveness of a teacher's…

The purpose of this quasi-experimental study was to compare the effects of new developmental statistics-based courses to traditional algebra-based developmental courses. The study used extant data from eight institutions and a matched sample of 2,041 students (Treatment, N = 748; Comparison, N = 1,293). All students enrolled in a treatment or…

Children's failure to reason often leads to their mathematical performance being shaped by spurious associations from problem input and overgeneralization of inapplicable procedures rather than by whether answers and procedures make sense. In particular, imbalanced distributions of problems, particularly in textbooks, lead children to create…

Using state-representative surveys, we investigated how familiar Texas, Ohio, Kentucky, and Massachusetts principals are with their state's K-12 standards, as well as the strength of their policy environments, using a policy attribute theory. We found relatively high levels of buy-in toward the idea of standards but only a general familiarity with…