Keywords
10-11 years, 12-13 years, 40-44 years, adult, asian ethnicity, attentive, awareness, berlin, blackboard, blond hair, boy, boys, casual clothing, caucasian appearance, chalkboard, cheerful, child, childhood, children only, class, classroom, comparison, concentration, conservation, day, earth science, education, elementary student, energy efficient light bulb, environment, environmental conservation, female, four people, front view, fuel and power generation, germany, girl, girls, global warming, head and shoulders, holding, horizontal, indoors, junior high, kids, learning, light bulb, listening, looking down, male, mature women, middle school, mixed age, multi-ethnic group, preadolescent children only, rear view, school, science, secondary school, series, side by side, sitting, smile, smiling, some under 18, standing, student, t-shirt, tank top, teacher, teaching, three-quarter length, toothy smile, woman, stock image, images, royalty free photo, stock photos, stock photograph, stock photographs, picture, pictures, graphic, graphics, fine art prints, print, poster, posters, mural, wall murals, 690023