Keywords
40's, 40-45, 40-50, 40s, 45-50, 50-55, 50-60, 55-59 years, 55-60, accomplishment, achievement, adult, america, american, americas, authentic, authenticity, blackboard, caldwell, caucasian, chalk, chalk board, chalkboard, cheerful, class, classroom, color, color image, colour, confidence, confident, continuing education, copy space, educating, education, educator, enjoyment, equation, fellow, fifties, fifty, forties, forty, front view, gaiety, gentleman, glad, gleeful, goal, gray, gray hair, grey, grey hair, guy, hair, hands in pockets, happy, higher education, horizontal, human, human being, id, idaho, indoor, indoors, information, inside, instructing, intelligence, jolly, knowledge, learning, lens flare, lighthearted, looking at camera, male, man, math, mathematician, mature adult, mature men, merry, mid life, mid-west, middle age, middle aged, middle-age, middle-aged, negative space, north america, occupation, one, one person, opportunity, people, person, photography, portrait, portraiture, posing, positive, professor, real people, satisfaction, school, schoolroom, self-assured, smile, smiling, standing, success, teacher, teaching, toothy smile, trigonometry, tuition, u.s, u.s.a, united states, united states of america, us, usa, waist up, waist-up, western european, white space, wisdom, work, working, 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, bld176073