I can but I don’t usually. Most students do not use homework or tests correctly, and have not developed good skills of self analysis. Because of this, assigning them more homework will not benefit them – they need to learn to maximize the benefit they can derive from the homework the have already been given, assuming they are doing it. For example most students try to churn out 30 questions in 30 minutes, because their object is just to get it done. Proper use of homework instead involves skipping the easy questions and spending half an hour struggling with four or five frustrating questions (whether you get them right or not) until they are completely understood.