Lack of training for school clinicians in evidence-based practices (EBPs) contributes to underutilization of such services for youth with attention-deficit/hyperactivity disorder (ADHD). Advances in web-based technology and videoconferencing have allowed for expanded access to and optimization of training. We describe the development and outcomes of a novel web-based platform for training school clinicians to gain skills in EBPs for school-age youth with ADHD. The training platform is adapted from an empirically supported, in-person training for a school-home behavioral intervention (Collaborative Life Skills program) and includes skill modules for working with teachers, parents, and students. Training methods include web-accessed manuals/handouts, skill example video clips, automated progress monitoring tools, and consultation/in-session coaching via videoconferencing. We gathered stakeholder qualitative and quantitative feedback during discovery and design phases of the iterative development. We then evaluated the usability, acceptability, fidelity and clinician and student outcomes of the remote training program. Focus group themes and qualitative feedback identified clinician preferences for remote training features (e.g., interactive, brief, role-plays/coaching methods), video tools (recorded samples of skills and therapy sessions), and progress monitoring tools (e.g., clear, easy to use). Clinician usability ratings of the platform were high with most components rated as moderately to very useful/easy to use. Clinician ratings of usability, fidelity implementing the treatment, and their EBP knowledge and confidence following training were favorable. Student's outcomes were similar to those achieved in prior studies of clinician in-person training. Results support the promise of remote, web-based clinician training for the dissemination of evidence-based practices.