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We devised and evaluated a multi-modal machine learning-based system to analyze videos of school classrooms for "positive climate" and "negative climate", which are two dimensions of the Classroom Assessment Scoring System (CLASS). School classrooms are highly cluttered audiovisual scenes containing many overlapping faces and voices. Due to the difficulty of labeling them (reliable coding requires weeks of training) and their sensitive nature (students and teachers may be in stressful or potentially embarrassing situations), CLASS- labeled classroom video datasets are scarce, and their labels are sparse (just a few labels per 15-minute video dip). Thus, the overarching challenge was how to harness modern deep perceptual architectures despite the paucity of labeled data. Through training low-level CNN-based facial attribute detectors (facial expression & adult/child) as well as a direct audio-to- climate regressor, and by integrating low-level information over time using a Bi-LSTM, we constructed automated detectors of positive and negative classroom climate with accuracy (10- fold cross-validation Pearson correlation on 241 CLASS-labeled videos) of 0.40 and 0.51, respectively. These numbers are superior to what we obtained using shallower architectures. This work represents the first automated system designed to detect specific dimensions of the CLASS. 

Thermal comfort (TC) – how comfortable or satisfied a per- son is with the temperature of her/his surroundings – is one of the key factors influencing the indoor environmental quality of schools, libraries, and offices. We conducted an experiment to explore how TC can impact students’ learning. University students (n = 25) were randomly assigned to different temperature conditions in an office environment (25◦C → 30◦C, or 30◦C → 25◦C) that were implemented using a combination of heaters and air conditioners over a 1.25 hour session. The task of the participants was to learn from tutorial videos on three different topics, and a test was given after each tutorial. The results suggest that (1) changing the room temperature by a few degrees Celsius can stat. sig. impact students’ self-reported TC; (2) the relationship between TC and learning exhibited an inverted U-curve, i.e., should be neither too uncomfortable nor too comfortable. We also explored different computer vision and sensor-based approaches to measure students’ thermal comfort automatically. We found that (3) TC can be predicted automatically either from the room temperature or from an infra-red (IR) camera of the face; however, (4) TC prediction from a normal (visible-light) web camera is highly challenging, and only limited predictive power was found in the facial expression features to predict thermal comfort.