One thing that often challenges teachers is the way that they group students. After working with students, they tend to have a group that they consider "low" and a group that they consider "high." Sometimes this designation comes as a result of testing. This is an area where mindsets need to change. When we think of students in these terms, we tend to determine their track and limit or expand our expectations--depending on the group.
I understand where this thinking comes from as it was taught to us as best practice for a while. However, as Jo Boaler and other researchers point out, it is not what is in the best interests of our students as it pigeonholes them into believing that they are not good at math or that math should come easily to them. Students who are consistently told that math comes easily to them often don't know what to do when it doesn't, and students who are led to believe that math is a struggle for them will want to avoid it because they are "no good" at it.
So how do we correct this mindset? There are a number of things that can be done. First, we need to be very deliberate when referring to students. We should work to no longer use terms like "high" or "low." What I find is that most of our students have strengths and weaknesses. Just because they have difficulty with computation doesn't mean that they don't have a great eye for geometric thinking.
Secondly, every effort should be made to not group our students every day by what we perceive to be their ability level. Students should be heterogeneously grouped so that they can all benefit from hearing the ideas and thinking of others. (Imagine if your principal always grouped teachers according to the strong teachers and the weaker teachers. How would the weaker teachers ever grow if they only had each other to get ideas from? And how would the stronger teachers develop better understanding of their craft if they had no one to think deeply with? Everyone brings something to the table.) Consider using visibly random grouping--an organizational structure researched, practiced, and encouraged by Peter Liljedahl as helping students become better problem solvers.
Next, use low-floor/high ceiling problems as much as possible with your students. From your opening routines to the rich tasks you ask your students to explore, find activities that all students can access and take to the level that they want. These tasks encourage creative thinking and offer may opportunities for rich mathematical discourse.
Being intentional in making these changes will lead to greater learning from our students and improved equity for all.