This project advances a Career & Technical Education employing a Horizontal Learning Model (HLM) integrates knowledge/skills across multiple technology areas within an authentic practice. The HLM organizes learning expansively through a series of graduated projects that allows students to contextualize learning across fields by integrating skills and knowledge across constituent domains progressively. We distinguish HLM from typical project-based learning by carefully designing the series of projects that satisfy the curriculum-based learning requirements of typical public school education while engaging students in pragmatic hands-on experiences. Our project integrates electronics design, micro-controller programming, digital fabrication and manufacturing. The project is run in the authentic settings of public high schools with differing characteristics (rural, urban, minority-majority) to understand how HLM may impact high school students' technology literacy, career preparedness, growth mindset, and sense of STEM/engineering interest and identity.