A method and system to provide video-based lectures accessible over a network by multiple PDA device types. To build a database, MIIME type PDA-compatible learning objects are generated from raw files (PowerPoint, MSWord, Macromedia Flash files) of an educator. The system includes a host server to provide an interactive server application to receive and convert raw files to audio/video presentations. Each learning object is classified according to a hierarchal educational structure and converted to a plurality of MIME files that match respective video platforms of a variety of PDA devices. The MIME files are tagged with authorship information, title, and/or other search parameters. A database stores these files on a network storage device for subsequent access by a learner's PDA. The network and system conveniently allow students to use their portable devices as a learning tool, and also enables a wider dissemination of expert instructional material throughout the world.