Digital learning tools like smartphones, tablets, and extended reality (XR) devices are increasingly accessible to students and teachers. These devices have the potential to be powerful educational tools and can simplify complex tasks, but they are often adopted without a full understanding of their effects on learners. This dissertation aims to evaluate how spatial technologies such as augmented and virtual reality (AR and VR), collectively referred to as extended reality, impact the learning process, and how these effects might depend on the characteristics of each individual learner. The research presented here expands on existing research by utilizing different categories of devices and multiple modes of visualization, analyzing their effects within three distinct settings and a diverse pool of participants. In our first analysis, we evaluated learning outcomes for students who used XR in a university classroom to explore key concepts from marine ecology and conservation. We found that students utilizing XR had significantly higher rates of learning achievement in a pre/post-test experimental design. While gender identity and recreational gaming habits had no significant relationship with learning achievement, women enjoyed the XR activity more than men and wished to use XR in educational contexts again in the future. In a second analysis, we evaluated learning outcomes for high school students who used gamified AR while visiting a public aquarium. In this informal educational setting, we again found that AR significantly improved learning outcomes, but we also observed a significant gender effect. Boys aged 14-18 displayed greater learning achievement than girls in response to the gamified mobile AR activity. In a third analysis, we evaluated the usefulness of XR tools for navigating a novel indoor environment. We found that stereoscopic AR improved participants’ abilities to navigate a novel indoor environment, compared to a control group with no assistance, but participants using monoscopic AR performed worse than the control group. When participants repeated the navigation task two weeks later without the use of a device, all groups demonstrated significant improvements in performance. The control group showed the greatest improvements, while participants in the stereoscopic AR group retained the least distance and time traveled. We found a significant relationship between navigational performance and the age of the participant, and a significant interaction between age and gender, but no relationships between navigational performance and gender or spatial thinking ability. Overall, this dissertation provides further evidence that XR technologies can be powerful educational tools. In all three chapters, we offer strategies and suggestions for educators who wish to implement XR in their classrooms or field trips.