The document discusses how the physical and social-emotional environment of a classroom can impact student and teacher performance. It states that enriched environments increase the brain's ability to connect and learn, while impoverished environments have the opposite effect. Enriched physical environments are described as attractive, engaging, and changing, while impoverished ones are unattractive, non-engaging, and unchanging. Enriched social-emotional environments are characterized as student-centered, risk-free, supportive, and collaborative, whereas impoverished ones are tense, threatening, and competitive. The document emphasizes that most learning comes from the classroom environment, not just the curriculum.