<p>Educational researchers and policymakers around the world have a strong interest in understanding the underlying reasons for the remarkable academic achievement of Chinese students in the Programme for International Student Assessment (PISA). Although teachers have a significant impact on student achievement, empirical evidence on teaching effectiveness in the Chinese education system has been scarce. This study uses the PISA 2012 Shanghai-China data and employs both multilevel models and quantile regression models to investigate effective teaching factors and their differential effects for students at different mathematics achievement levels. The results reveal the importance of cognitive activation and disciplinary climate as consistent, significant, positive predictors of secondary-school students' mathematics achievement in Shanghai, China. In addition, the positive relationships were more pronounced for low achievers. In contrast, student orientation and formative assessment demonstrate significant negative associations with mathematics achievement. Moreover, for student orientation, the negative association was larger for lower achievers whereas for formative assessment, the negative association was consistent except for very low or very high achievers.</p>