This study examined associations among a concurrent set of social-emotional strengths and school membership across the United States (N = 1,009) and Chinese (N = 747) students aged 9 to 11 years old. Results identified significant positive relations of school membership with four social-emotional strengths (i.e., gratitude, optimism, zest, and persistence) and a higher-order latent variable (covitality) in both countries, with optimism having the strongest association in both countries. Cross-culturally, U.S. students showed a stronger gratitude association with school membership whereas Chinese students had stronger zest and persistence associations with school membership. Implications for promoting school membership across cultural contexts are discussed.