Little-to-no research examines the provision of targeted mathematical interventions to students struggling with mathematics in a virtual environment. And yet, the global pandemic of 2020--extending into 2021--found schools in such a scenario. This article reports two studies in which researchers explored the intervention package of explicit instruction and the system of least prompts to teach elementary students (grades second through sixth) at-risk or struggling with mathematics online to solve mathematical problems at their individual area of struggle. In both studies, students learned to solve their targeted mathematical problems with 100% accuracy and over 90% independence. Students were able to maintain their skill accuracy at 80% or higher for two weeks post intervention. Also, they successfully generalized to solving problems in related mathematical areas without instruction.