Research tells us that school leadership is second only to teacher quality in its impact on student achievement. Successful principals focus on ensuring that their teachers are well-prepared and supported, but that is only the beginning of what it takes to ensure teachers continue to learn and improve—in turn improving the quality of learning for all students.

Infusing that mindset of continuous learning and improvement is not easy. Even at the best schools, principals must navigate many pitfalls to impart this vision to faculty. Let’s examine seven deadly sins, or critical mistakes, and discuss solutions that can help increase morale as well as test scores-because the two go hand in hand.

Mistake #1: Not Valuing the Best Teachers

According to a recent study by The New Teacher Project (TNTP), when a top teacher leaves the average school, only 1 in 6 potential replacements will be of similar quality. In a low-performing school, only 1 in 11 potential replacements will measure up. In other words, when a great teacher leaves, a school is almost guaranteed to hire a less effective replacement. TNTP calls these top-performing teachers Irreplaceables, and principals ignore them at their peril. School leaders should first ask themselves who their best teachers are—and if they do not know, they must identify them. They should think about what they are doing to retain these invaluable educators, including whether or not they are ushering out low performers. From there, they should focus on targeted support for these Irreplaceables, including regular, positive feedback and help to identify areas of further development and potential leadership opportunities—not just added duties. In places without formal teacher leadership roles, that could mean putting a high-performing teacher in charge of something important or involving them in some of the ideas suggested below. And if you believe a teacher is high performing and irreplaceable, tell him or her so!

Mistake #2: Not Motivating Staff with Positive Feedback

Feedback is vital for all teachers, especially as data-driven decision making has become an integral part of school reform efforts. However, “having data does not mean that it will be used appropriately or lead to improvements,” according to nonprofit research organization the RAND Corporation. Ensure that all teachers receive feedback and opportunities to develop their craft. Let your best teachers help to analyze the data and ask them how they suggest approaching the weak areas. Even data that shows the need for improvement can be used to motivate teachers-instead of saying “we’re still below where we need to be,” try, “we need only three more math scores to be at our expected goal!”

Mistake #3: Presenting High-stakes Tests as a Burden

You probably don’t hear teachers, parents, or students complain about the SAT or ACT. That’s because these tests are respected gateways to college. And to be fair, in most states, the first high-stakes assessments were disappointments. But most assessments today have been replaced by those that better measure critical skills and concepts that mirror what students need to be successful in college and life. So, it’s up to school leaders to change perceptions. Do we want American students to perform as well as their counterparts in other countries? Start by looking in the mirror: Are you negative about high-stakes tests? Work with your staff, parents, and students in changing their image. Tell your Irreplaceables you need their help in changing the perception and environment. Focus on state, national, and international rankings. Get coaches involved in motivating students—they love competition! Involve National Honor Society students and student council officers; let them motivate younger students. If teachers think positively about these tests, they will be motivated to strive for excellence; students will follow, and scores will increase.

Mistake #4: Not Knowing Exactly Where Problems Exist

The ability of high-stakes tests to help teachersidentify strengths and weaknesses in teaching andlearning has greatly improved. Though they have little time and many meetings, all teachers need tobe able to work with data. This data needs to be in teachers’ hands, or why gather it in the first place? Many teachers look only at the bottom line. Show them how to drill down into the valuable informationin the item analyses. Ask your Irreplaceables to present a model lesson touching on a specific skill where itemanalyses show that students have struggled. When teachers review the data for the entire department, identify peers who have the highest scores. Ask them to provide a lesson to the department on that particular skill.

Mistake #5: Misuse or Mismanagement of School Time

Principals must empower teacher sto use time more creatively. Encourage you best teachers to experiment with blended learning and the flipped classroom so valuable classroom time can be spent working in small groups and checking for understanding—not delivering lectures that students could watch online. As the building leader, you can also develop strategies to minimize disruptions to learning time, from the mundane (policies governing field trips and pep rallies) to the deliberate and pervasive (using email or text alerts instead of the intercom or pulling teachers out of the classroom). Ask your Irreplaceables to tape one 20-minute lecture per week. How? Let a student videotape it. Buy your teachers tripods for phones. Set up the teacher’s phone and tape the lecture. Then, instead of spending 20 minutes lecturing, the teacher can spend that time in one-to-one conferences with students, assessing students’ work, row-running, or creating pacing plans to differentiate. Use technology not to replace the teacher, but to replace the time!

Mistake #6: Assuming Traditional Tools and Administrative Pressure Improve Teaching and Learning

Unfortunately, educators find themselves using traditional approaches with a student population of digital natives. Today’s educators need subject- and course-specific professional development that supports them as they approach the blended learning environment of the modern classroom, whether it is brick-and-mortar, online, or a hybrid of the two. Why choose only traditional professional development that requires travel and full days of generic content when you can give your staff professional development tools that are available 24/7 on demand? Combine traditional PD with digital PD. An added benefit: When teachers participate in digital PD, they learn how to rethink, create, and apply digital activities in their own classrooms.

Mistake #7: Not Involving the Best and Brightest Teachers in the Big Picture

Research suggests that it can take up to three years for teachers to internalize new skills and content. Ensuring that teachers don’t just receive one-and-done training that varies year to year requires principals to articulate a vision for teaching and learning in their building, and to stick to it. But that’s a role they shouldn’t take on alone. Give your Irreplaceables ownership and an opportunity to lead by bringing them into identifying, developing, and supporting this vision. Use established structures that require teacher involvement—e.g., school improvement and accreditation committees—that too often are considered checklist exercises in compliance.Internal and particularly external review processes can help school leaders and teachers work together to discover the underlying causes of all aspects of the school’s performance—from student achievement and instruction to use of resources. That work, which also draws in other stakeholders, leads to the development of a powerful long-term plan that participating teachers can share with their peers. That kind of participation and leadership from teachers will not only improve morale and understanding among faculty, but will likely result in a better vision for the school.

Deborah Louis, PhD, is president and CEO of the Center for Educational ReVision and owner of the Jane Schaffer Writing Program.