The SNAPSHOT study seeks to measure Sleep, Networks, Affect, Performance, Stress, and Health using Objective Techniques. It is an NIH-funded collaborative research project between the Affective Computing and Collective Learning groups, and Harvard Medical School's Brigham & Women's hospital. Since fall 2013, we've run this study to collect one month of data every semester from 50 undergraduate students who are socially connected. We have collected data from about 250 participants, totaling over 7,500 days of data. We measure physiological, behavioral, environmental, and social data using mobile phones, wearable sensors, surveys, and lab studies. We investigate how daily behaviors and social connectivity influence sleep behaviors and health, and outcomes such as mood, stress, and academic performance. Using this multimodal data, we are developing models to predict onsets of sadness and stress. This study will provide insights into behavioral choices for wellbeing and performance.