The study took place in 53 first-grade classrooms from nine elementary schools in three school districts in Oregon. One school district was located in the urban area of Portland, and two districts were in suburban areas of western Oregon.
The study included nine elementary schools with 36 teachers and 53 first-grade classrooms. A total of 460 students were randomly assigned to one of three conditions: 92 were assigned to receive 2:1 Fusion, 230 were assigned to receive 5:1 Fusion, and 138 were assigned to the comparison group. In this review, the group receiving 2:1 Fusion is the intervention group and the group receiving 5:1 Fusion is the comparison group. The no-services comparison group is not included in this review. Among the full study sample of 460 students, approximately 54% were female, 14% were English learners, and 17% received special education services. Sixty-five percent were White, 3% were Asian, 2% were Black, 1% were Native American, 8% were of multiple races, and 21% did not report race. Twenty-one percent were Hispanic or Latino.
Fusion is a 60-lesson, Tier 2 first-grade mathematics intervention focused on whole number understanding. The Fusion 2:1 intervention was delivered in a small-group format (two students per interventionist), with lessons lasting for 30 minutes. The study administered the program five days per week for 12 weeks. Fusion is a supplemental intervention, so instruction did not interfere or replace regular mathematics instruction. Instruction began in the early winter and ended in the spring. The intervention aims to build students’ proficiency of whole number knowledge, specifically in operations and algebraic thinking, and number and operations in base-10. Lessons 1 through 30 focus on building proficiency in modeling, writing, and sequencing two-digit numbers. Lessons 31 through 60 focus on problem solving and two-digit addition and subtraction problems and compare two-digit numbers.
Students in the 5:1 Fusion comparison group received the same intervention as students in the intervention group, except in a small group format with five students per interventionist.
Support for implementation
All interventionists participated in two four-hour professional development workshops delivered by project staff. They also received, on average, two coaching visits from coaches, involving direct observations and feedback on instructional quality and fidelity.