A critical gap exists between research-driven early reading disability (RD) prevention efforts and practice. To help bridge this gap, we describe the development of a technology-based tool to help preschool teachers implement responsive "assessment-guided" practices (screening, intentional teaching, and reflective monitoring, evaluation, and individualizing of learning progress) to reduce children's risk for RD prior to school entry. The tool comprised tablet and website embedded supports for initiating and sustaining these practices, such as: online assessment and reports, teacher training, downloadable classroom materials, implementation guidance, and progress monitoring capabilities. We also report preliminary findings from four tool-implementing classrooms (n = 33) and four non-implementing classrooms (n = 37) for evaluating the impact of this technological RD prevention approach. Over 6 months, prekindergarten teachers thrice administered a tablet screener, implemented 1-h strategic classroom activities (Circle, Story, Play, and Center) 9 days per month, and engaged in systematic, ongoing monitoring of learning and individualization of supports for children with identified RD risk. Statistically significant between-group mean differences in spring pre-reading performance was found between tool implementing and comparison "business-as-usual" non-implementing classrooms. By spring, only 13.5% of children in tool-implementing classrooms remained at-risk for RD (down from 45.9% in the fall) compared to 48.6% of children in non-implementing classrooms (down from 56.8% in the fall). In addition, teachers positively rated their implementation experience. Our findings suggest that with embedded technological support, prekindergarten teachers can feasibly and effectively engage in evidence-informed practices to systematically reduce children's risk for RD.