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Code quality is of universal concern among educators. Refactoring code, i.e., revising the structure of a program without changing its behavior is one approach for improving code quality. Numerous software tools have been created to help students refactor the code they write. Only a few software tutors have been reported in literature that help students proactively learn code quality by solving refactoring problems. But they suffer false positive and false negative grading issues because they allow freehand coding. We investigated whether refactoring tutors that do not allow freehand coding could be used to help students learn about non-trivial anti-patterns. We developed and deployed two software tutors for refactoring problems that are based on the principle of “refactoring without rewriting code”, and cover a subset of refactoring problems that can be solved using only deletion, duplication, reordering and token-wise editing of lines of code. We investigated whether students needed to learn the anti-patterns covered by the tutors and whether they benefited from using the tutors. In this experience report, we start by describing the tutors – the list of refactoring concepts covered, the user interface, grading, feedback and usage. We report our experience using the tutors over three semesters, which confirmed that both introductory and advanced students needed and benefited from using the tutors despite the limitations of the tutors’ coverage. We reflect on what worked and what did not. The tutors currently cover C++, Java and C#. They are available for free for educational use on the web at auglets.org.