It's both true and not racist. It would be racist to attribute that the observed behavior is due to genetic, ethnic or cultural reason.
In my opinion racism is about making value judgements across ethnic lines. First you draw a line along an ethnic distinction (maybe Chinese/Westerners). Second you make value judgement in the form of "one side has higher character". And third, possibly, you apply that value judgement to some other area or act on it.
Without a value judgement there can be no racism. Now, plagiarism is mostly seen as a negative behavior, but I don't get the feeling that the OP wanted to make a point about the Chinese students' character or their virtues.
In my opinion racism is about making value judgements across ethnic lines. First you draw a line along an ethnic distinction (maybe Chinese/Westerners). Second you make value judgement in the form of "one side has higher character". And third, possibly, you apply that value judgement to some other area or act on it.
Without a value judgement there can be no racism. Now, plagiarism is mostly seen as a negative behavior, but I don't get the feeling that the OP wanted to make a point about the Chinese students' character or their virtues.