The study took place in a southern California public school district.
Of the 193 third-grade children randomized to conditions, 83 were female and 110 were male (page 152). The sample included 116 White, 30 Hispanic, 13 African-American, 12 Asian, and 22 mixed ethnicity students. As determined by free lunch participation, parent education, and occupation, the sample ranged from lower middle class to upper middle socioeconomic status (SES; the average was low to middle SES). Participants were identified as at risk for persistent difficulties in problem-solving performance (as determined by norm-referenced story problem-solving math tests); however, most students in the sample were not diagnosed with specific learning disabilities in mathematics. The average age in months of students identified as at risk for math difficulties (MD) was 103.53 (SD=5.98), and the average age in months of students identified as not at risk for math difficulties (non-MD) was 104.41 (SD=5.48).
These sample characteristics are not provided by study condition, and they are not provided by classification (MD, non-MD). Therefore, there is not information on the specific sample for this contrast (Verbal + Visual intervention group vs Materials only intervention group contrast).
For this contrast, the intervention condition is the verbal + visual intervention group. This condition included 20 scripted lessons administered by tutors (graduate students or paraprofessionals) over a period of 8 weeks. Each lesson was 30 minutes in duration and administered 3 times a week in groups of 2-4 children. At the beginning of each lesson, children received a booklet, where they recorded all responses. Each lesson consisted of four phases. The warm-up phase (3-5 minutes) included calculation of problems and puzzles based on problems that used geometric shapes. The direct instruction phase (about 5 minutes) began with the tutor reading or reviewing rule cards or strategies. Students learned a specific strategy for solving problems that included both visual and verbal cues. For the verbal steps, students were taught to identify (1) the question sentence and underline it, (2) the sentences with the numbers and circle the numbers, (3) the key word and put a square around it, and (4) irrelevant sentences and cross them out. From there, students would figure out which operation was needed (addition, subtraction or both) and solve the word problem. For the visual steps, the students learned two diagramming strategies: one for parts comprising a whole and one for comparing quantities. Finally, students were taught to use the diagrams with the numbers found in the word problem and identify the missing information. The third phase (10 minutes) was guided practice, during which students completed three practice problems and received tutor feedback. Each session ended with the fourth phase, independent practice (10 minutes) in which students solved three word problems on their own without feedback.
For the contrast in this review, the comparison condition is the materials only intervention group. The structure and timing of the comparison group sessions was the same as the intervention group. However, students in the materials only condition did not participate in activities with overt strategy instruction.
Support for implementation
Independent observers (including a post-doctoral student, a non-tutoring graduate student, and the project director) evaluated the accuracy with which each tutor implemented instructional sequences during six randomly selected instructional sessions.