I have a challenge for teachers and professors of the world. In particular, this challenge is targeted toward teachers of advanced high school courses on up into higher education but it can apply elsewhere. The challenge is to give a test, quiz, or assignment that you would give your students to your colleagues. If your colleagues are missing problems, then your test, quiz, or assignment is not at a reasonable difficulty. As another teacher or professor, your colleague should know the material better than you expect the students to know the material.
The reason I am making this challenge is because there are cases when material appearing on assignments simply does not belong there. Examples include many proofs. In particular, I refer to proofs that do not appear in lecture and course material. Of those, I refer to those proofs that do not deviate in a patterned way from proofs that are shown. When these proofs were originally formulated, which is a feat you are asking your students to repeat when the desired proof meets the mentioned qualifications, it took much longer than a day. In some cases, you are asking students to repeat such an amazing feat in less than an hour. Does that seem right?
If you are a professor or teacher and you take this challenge, please let me know your results. Additionally, if you have a differing view on this issue, let me know. I am interested in education and have thought about being a teacher or professor someday, likely after a career in my chosen field.