At least among high schoolers, according to this study. Davide Cantoni, Yuyu Chen, David Y. Yang, Noam Yuchtman, and Y. Jane Zhang exploit the staggered rollout of a new Chinese curriculum to identify the effectiveness of ideology brainwashing. It worked!
But it is not surprising at all. Teenagers, unless experiencing direct challenges, take in whatever teachers and parents say. The real question is, once these teenagers become twenty- or thirty-something, do they still believe in the same thing? Is there going to be a ideological backlash?
I used to receive similar brainwashing curriculum in Taiwan. My peers in college were those ones who did the best in school, just like those in the study at Pecking University. I observe that most of my classmates belong to the two extremes: either still cherish the values taught in high school by now or completely dismiss stuff instilled by the authoritative government. No middle ground.
So I expect these Chinese students are about to see this backlash. And I also expect a big part of them will become the staunchest supporters of the Chinese Communist Party rule. China is about to have a big change.