These are the Teacher Line PBS.org questions for mathematical thinking.
They are listed by slide according to specific categories. You place Post-it notes on the blank slides and copy. Questions will print directly on to sticky notes so that you can simply peel them off and place them on student work as feedback. You can even have students use them for peer feedback.
I sometimes print duplicates of specific slides depending on the topic or the students I am working with.
I have included slide 13- which has my six favorite questions
I have included an option 14th slide for you to edit if you want to create a specific slide with your favorite questions.