Observations of the first day of class are reported for 23 introductory STEM courses at three different institutions. The topics instructors discuss and the noncontent Instructor Talk they use on the first day are described. These results uncovered variation in instructor actions on the first day and can help instructors plan this day.

Background and Aims The ranunculid model system Aquilegia is notable for the presence of a fifth type of floral organ, the staminode, which appears to be the result of sterilization and modification of the two innermost whorls of stamens. Previous studies have found that the genetic basis for the identity of this new organ is the result of sub- and neofunctionalization of floral organ identity gene paralogues; however, we do not know the extent of developmental and molecular divergence between stamens and staminodes. Methods We used histological techniques to describe the development of the Aquilegia coerulea ‘Origami’ staminode relative to the stamen filament. These results have been compared with four other Aquilegia species and the closely related genera Urophysa and Semiaquilegia. As a complement, RNA sequencing has been conducted at two developmental stages to investigate the molecular divergence of the stamen filaments and staminodes in A. coerulea ‘Origami’. Key Results Our developmental study has revealed novel features of staminode development, most notably a physical interaction along the lateral margin of adjacent organs that appears to mediate their adhesion. In addition, patterns of abaxial/adaxial differentiation are observed in staminodes but not stamen filaments, including asymmetric lignification of the adaxial epidermis in the staminodes. The comparative transcriptomics are consistent with the observed lignification of staminodes and indicate that stamen filaments are radialized due to overexpression of adaxial identity, while the staminodes are expanded due to the balanced presence of abaxial identity. Conclusions These findings suggest a model in which the novel staminode identity programme interacts with the abaxial/adaxial identity pathways to produce two whorls of laterally expanded organs that are highly differentiated along their abaxial/adaxial axis. While the ecological function of Aquilegia staminodes remains to be determined, these data are consistent with a role in protecting the early carpels from herbivory and/or pathogens.

Introductory STEM courses represent entry points into a major, and student experiences in these courses can affect both their persistence and success in STEM disciplines. Identifying course-based student concerns may help instructors detect negative perceptions, areas of struggle, and potential barriers to success. Using an open-response survey question, we identified 13 common concerns expressed by students in introductory STEM courses. We converted these student-generated concerns into closed-ended items that were administered at the beginning and middle of the semester to students in 22 introductory STEM course sections across three different institutions. Students were asked to reflect on each item on a scale from very concerned to not concerned. A subset of these concerns was used to create a summary score of course-based concern for each student. Overall levels of student concern decreased from the first week to the middle of the semester; however, this pattern varied across different demographic groups. In particular, when controlling for initial concern and course grades, female students held higher levels of concern than their peers. Since student perceptions can impact their experiences, addressing concerns through communication and instructional practices may improve students’ overall experiences and facilitate their success.

The instructional practices used in introductory college courses often differ dramatically from those used in high school courses, and dissatisfaction with these practices is cited by students as a prominent reason for leaving science, technology, engineering, and mathematics (STEM) majors. To better characterize the transition to college course work, we investigated the extent to which incoming expectations of course activities differ based on student demographic characteristics, as well as how these expectations align with what students will experience. We surveyed more than 1500 undergraduate students in large introductory STEM courses at three research-intensive institutions during the first week of classes about their expectations regarding how class time would be spent in their courses. We found that first-generation and first-semester students predict less lecture than their peers and that class size had the largest effect on student predictions. We also collected classroom observation data from the courses and found that students generally underpredicted the amount of lecture observed in class. This misalignment between student predictions and experiences, especially for first-generation and first-semester college students and students enrolled in large- and medium-size classes, has implications for instructors and universities as they design curricula for introductory STEM courses with explicit retention goals.