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In Chicago Public Schools there is a need to provide guidance to schools on placing students into an intro-level CS class (ECS) or the more difficult AP CSP as a student’s first CS class. Previous work created a placement exam based on the ECS curriculum to identify students prepared for AP CSP without taking ECS. This analysis found that after controlling for many variables including GPA, sex, attendance at a selective enrollment school, and perceived value of CS, that the placement score was positively associated with the probability of a student passing the AP CSP exam. 

Scientific outreach to K12 education typically centers around the direct dissemination of scientific findings or by engaging students in citizen science data collection. Rather than viewing science outreach purely through the lens of knowledge transmission or through the lens of specific data collection practices, we present a view of science outreach as a bridge to bring K12 students into ecologists’ communities of practice. We exemplify this outreach model using the Luquillo Long-Term Ecological Research (LTER) Schoolyard program as an example. The schoolyard program brings middle-school and high-school students into the Luquillo LTER community of practice through authentic scientific inquiry with long-term ecological data. 

We used Manna’s theory on borrowing strength to examine the influence of local and national idea champions seeking to broaden the participation of K-12 students in computer science. Concepts from Manna’s model were applied to analyze interview data gathered from idea champions at the national and local levels. We identified examples of borrowing strength that not only highlighted the importance of individual policy entrepreneurs but also elevated the importance of community building. We introduce the concept of building strength to highlight how idea champions strategically supported capacity-building activities at a different level in the federal system prior to borrowing strength. 

Though much is known about fungal importance to forest health, there is very little information about factors that impact recovery times of soil fungal communities after a fire. Soil samples were taken from burn sites within one ecotype of temperate coniferous forest in Utah over a 20-year chronosequence. Sites were selected from available historic burns and were similar in plant community structure, elevation, slope, and aspect. Fungal DNA from these samples was compared to soil from paired unburned sites nearby to measure community similarity and estimate soil fungal recovery rates. Differences between paired burned and unburned sites remained fairly stable over a decadal timescale overall, but fungal community structure was found to recover more quickly in areas with a higher average annual temperature. A significant positive correlation in community recovery was seen in areas with a difference of as little as 2 °C per year. The only other environmental variable that significantly interacted with time since burn was annual mean precipitation. As global temperatures increase, alpine fires are increasing as well, but these results suggest that fungal community recovery time will be shortened under new climate scenarios. 

Abstract Quasi-periodic eruptions (QPEs) are luminous bursts of soft X-rays from the nuclei of galaxies, repeating on timescales of hours to weeks^1–5. The mechanism behind these rare systems is uncertain, but most theories involve accretion disks around supermassive black holes (SMBHs) undergoing instabilities^6–8or interacting with a stellar object in a close orbit^9–11. It has been suggested that this disk could be created when the SMBH disrupts a passing star^8,11, implying that many QPEs should be preceded by observable tidal disruption events (TDEs). Two known QPE sources show long-term decays in quiescent luminosity consistent with TDEs^4,12and two observed TDEs have exhibited X-ray flares consistent with individual eruptions^13,14. TDEs and QPEs also occur preferentially in similar galaxies¹⁵. However, no confirmed repeating QPEs have been associated with a spectroscopically confirmed TDE or an optical TDE observed at peak brightness. Here we report the detection of nine X-ray QPEs with a mean recurrence time of approximately 48 h from AT2019qiz, a nearby and extensively studied optically selected TDE¹⁶. We detect and model the X-ray, ultraviolet (UV) and optical emission from the accretion disk and show that an orbiting body colliding with this disk provides a plausible explanation for the QPEs. 

This work is part of an ongoing partnership that seeks to create a sustainable infrastructure to support GIS-infused instruction in a large urban school district. In this paper, we report an illustrative cross-case comparison of two teachers’ approaches to infusing GIS in their courses. The goal of this analysis is to examine how GIS-infused instruction is adapted in different contexts and to consider the affordances of divergent approaches. Findings illustrate the relationships among organizational context, individual and collective context, particularly teacher identity, and instructional practice in the work of spreading GIS-infused instruction. We also discuss key lessons learned in our partnership thus far and implications for district-level partnerships focused on spread and scale. 

Geographic information systems (GIS) is valuable as a teaching and learning tool and will play a key role in the careers of current K-12 students (NRC, 2006). However, little work has been done to understand effective approaches to integrating GIS into content instruction. In this paper, we discuss the adaptation of the Learning for Use model, a framework for the design of technology-supported, content-driven inquiry tasks (Edelson, 2001), for the context of GIS-infused content courses. Using a design-based research approach, we developed a set of design principles that reflect key elements of effective GIS-driven content instruction, which guided the adaptation of the design framework. The goal of this work is to develop a set of supports to scaffold the co-design and implementation of GIS-infused content courses that will inform a general design model of infusing GIS into content courses. 

Thousands of students around the country have participated in activities using the Data Jam model, creating poetry, songs, videos, or sculpture to improve their data literacy, gain knowledge of local science research, and creatively express their findings. This article introduces the Data Jam model and how teachers can use it in classroom or after-school settings, supported by vignettes of student projects and feedback from teachers and students. 

Abstract We present the discovery and extensive follow-up of a remarkable fast-evolving optical transient, AT 2022aedm, detected by the Asteroid Terrestrial impact Last Alert Survey (ATLAS). In the ATLASoband, AT 2022aedm exhibited a rise time of 9 ± 1 days, reaching a luminous peak withM_g≈ −22 mag. It faded by 2 mag in thegband during the next 15 days. These timescales are consistent with other rapidly evolving transients, though the luminosity is extreme. Most surprisingly, the host galaxy is a massive elliptical with negligible current star formation. Radio and X-ray observations rule out a relativistic AT 2018cow–like explosion. A spectrum in the first few days after explosion showed short-lived Heiiemission resembling young core-collapse supernovae, but obvious broad supernova features never developed; later spectra showed only a fast-cooling continuum and narrow, blueshifted absorption lines, possibly arising in a wind withv≈ 2700 km s⁻¹. We identify two further transients in the literature (Dougie in particular, as well as AT 2020bot) that share similarities in their luminosities, timescales, color evolution, and largely featureless spectra and propose that these may constitute a new class of transients: luminous fast coolers. All three events occurred in passive galaxies at offsets of ∼4–10 kpc from the nucleus, posing a challenge for progenitor models involving massive stars or black holes. The light curves and spectra appear to be consistent with shock breakout emission, though this mechanism is usually associated with core-collapse supernovae. The encounter of a star with a stellar-mass black hole may provide a promising alternative explanation.