"课税处理方法" can be translated into English as "tax treatment methods" or "methods of tax handling".
"Tax treatment methods" is a more formal and commonly used term in financial and tax contexts, referring to the various approaches or rules applied in calculating and imposing taxes.
"Methods of tax handling" is a more straightforward translation that conveys the idea of the techniques or procedures used in dealing with taxes.
Both expressions are accurate, and the choice between them may depend on the specific context and the intended audience.