We present ST ELT (Smart Technologies to Enhance Learning and Teaching) a toolkit devoted to produce Augmented Reality applications for teaching and learning based on RFID technology and Artificial Tutoring Systems. We also provide a general description of three applications that embed ST ELT software libraries: a) Block-Magic: an environment to enhance well-known educational materials used in the kindergartens; b) Walden Pecs Communicator: a system to enhance communications of severely cognitive disabled people; c) Roboprof: an environment for science divulgation currently used in Science Centers.