Just because someone (whether it is Rowling, Newton, or someone else) had done something racist does not necessarily make all of their works to be racist. You

Just because someone (whether it is Rowling, Newton, or someone else) had done something racist does not necessarily make all of their works to be racist. You should write non-racist curricula (if possible), but the way to do this is to avoid making statements that discriminate against someone, rather than to avoid the use of anyone's name or works or anything else just because they are racist or are affiliated with someone or were in the past racist or because the words are similar or for other reasons. However, I do think that it is sensible to avoid making assumptions of knowing something that you do not know, and to make the text clear if some part of it is possibly unclear. (Avoiding mentioning Harry Potter and J.K.Rowling probably helps with clarification, but avoiding mentioning Isaac Newton probably is worse and makes it less clear, I think.) In the case of hangman, I had generally just avoided to draw a picture of hanging or anything and just mention, if you tried a specified number of wrong letters before trying all of the correct letters, then you lose; if you entered all of the correct letters before that then you will win.