Despite an extensive amount of research examining students' perceptions of alternative laboratory experiences, little focus has been aimed at the perceptions of adult learners. This two-phase mixed-methods study investigated the preferred at-home laboratory experience, and the factors that played a significant role in the user experiences, of adult learners in an online, undergraduate science course. A modified version of Brooke's (1996) System Usability Scale (SUS) was utilized in Phase I (quasi-experimental crossover phase); students self-selected between an at-home hands-on (AHHO) and virtual (VL) laboratory experience in Phase II. The SUS is a normed, validated, product-agnostic questionnaire that measures the quality of the user experience based on factors that support adult learners' needs (effectiveness, efficiency, engagement, error tolerance, ease of use, and self-efficacy). Both phases showed no significant difference in preference for the AHHO or VL experience; and both the quantitative and qualitative strands showed that effectiveness, engagement, and ease of use were the most important factors for a good laboratory experience. The findings imply that the laboratory medium (AHHO or VL) is not as important to adult learners as the clarity of the laboratory instructions and the usability of the laboratory materials; and that a blend of AHHO and VL experiences would be the most beneficial to learners. Moreover, as the self-selection and crossover data arrived at the same conclusion, the modified SUS proved to be an effective instrument to measure the perceived usability, its sub-factors, and the quality of the user experience for laboratory experiments. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]