This study aims to examine the temporal evolution and changes of research interests and trends in the educational augmented reality (AR) literature. To this end, 3718 articles published in the 2003-2022 period and indexed in the Scopus database were analyzed through machine learning-based semantic topic modeling and descriptive analysis. The findings indicate a notable upswing in studies on educational AR, particularly since 2015. The articles were categorized into eleven primary themes through topic modeling analysis. The three most prevalent topics in terms of volume are "Augmented Reality in Education and Cultural Heritage", "Medical Education and Patient Care", and "Enhancing Safety and Information in Food Consumption". Observations across different times reveal that "Augmented Reality in Electrical and Electronic Systems" and "Gesture-Based Instruction and Maintenance" were studied in the initial periods. Since 2015, there has been a notable increase in applications falling under the "Serious Games" category. The least voluminous and slowest-evolving topics are identified as "Serious Games for Children with Autism Spectrum Disorder", "Augmented Reality in Chemistry and Biology Laboratories", and "Augmented Reality for Safe and Efficient Driving". Considering the recent momentum gained by these topics, it is anticipated that they will become popular topics for future studies. This study represents a significant milestone as the first and most comprehensive research using machine learning in its field, not only explaining the current state of the field but also providing valuable information for future research efforts.