There are significant differences in the impact of color in teaching space on the concentration of primary school students aged 6-12. Twenty subjects from grades 1-6 completed the same learning task under four RGB standard color backgrounds: red, yellow, green, and blue. FaceReader facial expression data, SUS and 5-point Likert subjective scores, and task scores were collected. The concentration index, positive emotion ratio, and test score s under green (0128,0) and blue (0,0255) conditions were signifi cantly higher than those under red and yellow conditions (p<0.01); Red and yellow environments induce high levels of arousal and interfere with sustained attention. The results suggest that using short wavelength cool colors on the classroom interface can reduce physiological activation levels, support the transition from break to classroom state, and provide quantitative basis for color design in primary school learning spaces.