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Coronavirus (COVID-19) information

Laura Hertzler

Head of School

Ms. Laura joined Keystone in 2011. Ms. Laura is responsible for the vision, management ...

July 16, 2021

Dear Keystone Families,

We hope this letter finds you enjoying summer days together and excited for a return to school! We are eager to welcome our students, and have been busy this summer with campus improvements, planning, and preparation for another wonderful school year.

Over the last few weeks, we have been working to update our mitigation plan and safety protocols. We thank you for your support and patience while we reviewed the most up to date information available from health officials to ensure our students, staff, and families stay healthy. Please read the updated mitigation plan carefully as there have been changes. Please note that newly enacted legislation no longer allows schools to require that face coverings be worn during school hours or on school property.  Keystone continues to strongly recommend families send their children to school with face coverings. Both students and staff are encouraged to wear face coverings during the school day if they choose to do so.

Please watch for your welcome email to be sent by July 23rd with classroom assignments (if applicable), updated drop-off and pick-up procedures and Meet the Teacher sign ups. Meet the Teacher time slots will be available for students new to Keystone and those moving up to the next level (e.g. Children’s House to Lower Elementary) from July 26th – 29th starting at 2:30pm, with the last appointment of the day at 4:30pm.

Should you have any questions or concerns, please feel free to contact us and we will be happy to help. As a new year begins, we are grateful for our Keystone family and we look forward to the learning and excitement the new school year brings!

In Health and Peace,

Laura Hertzler              Stefan Linder
Head of School             Associate Head of School


April 20, 2021


Dear Keystone Families,

As many of you may have heard, Governor Ducey issued an Executive Order yesterday, April 19th, rescinding the order requiring masks in Arizona K-12 schools. The order allows each school to create and/or maintain individual policies and guidelines. The Centers for Disease Control and Prevention and public health officials continue to recommend the wearing of masks in schools along with following mitigation strategies to ensure a safe learning environment.

As such, there will be no changes to the Keystone Montessori facial covering policy for the remainder of the school year.

The Keystone Mitigation Plan has provided guidance throughout this school year. For the continued health and safety of our community, all students, staff and visitors will still be required to wear facial coverings while on campus and at school activities.

As the school year draws to a close, we ask that you continue to follow our facial covering policy. It is our combined efforts that have made our Mitigation Plan so successful in maintaining a healthy campus.

In Health and Peace,

Laura Hertzler
Head of School
Keystone Montessori


March 28, 2021

Dear Keystone Families,

Earlier this week, Gov. Ducey issued Executive Order 2021-06, rescinding county and municipal mask mandates and business restrictions established in prior Executive Orders. However, per the Arizona Department of Health Services, the AZDHS Emergency Measure requiring mask use in K-12 schools remains in effect. The Arizona State Board for Charter Schools informed us that we are to continue enforcing our mask mandate, as required in the aforementioned Emergency Measure. Masks must be worn on school campuses, on school buses and during school-associated activities by all students, faculty, staff, contractors, and visitors.


February 25, 2021


Dear Keystone Families, 

We are pleased to announce that we will resume in-person instruction for charter students on Monday, March 1st! 

The Keystone Administration and staff thank each of you for your patience, support, and grace throughout this school year. The decision to return to in-person instruction was made with careful consideration of the following: 

  • The steady decline of the ADHS County-level school benchmark numbers. While the recommended delivery model is still “Virtual”, the decline of all three benchmarks has remained consistent over the last five weeks. Trends indicate the decline will most likely reach the "Hybrid" level by next Thursday. 
  • The most recent CDC guidelines and recommendations regarding the safe return to in-person instruction and the most recent update from Superintendent of Public Instruction, Kathy Hoffman.
  • The ability for Keystone staff to receive the COVID—19 vaccination.
  • Continued commitment to the Keystone mitigation plan for the safety of our students, families, and staff.
  • Consultation with the Maricopa County Department of Public Health. 

As we prepare to welcome our students back to in-person instruction, there is a feeling of hope and excitement spreading throughout the campus. Students, both in-person and distance learning, will continue to be supported on their Montessori journey. We look forward to seeing you on Monday and are overjoyed to return to in-person instruction. We will be resending the mitigation plan no later than this weekend for your review.* 

In Health and Peace, 

Laura Hertzler & Stefan Linder 


*For parents with student(s) returning to campus for the first time this school year, we are hosting an informational meeting tomorrow, February 26th, at 5:00 pm. 

Zoom Meeting ID: 918 657 5932

Pasword: 2r51nt


February 20, 2021

Dear Keystone Families, 

Throughout the COVID-19 pandemic Keystone has held the safety of its students and staff at the forefront of every decision. We will continue to support families choosing to continue distance learning as we prepare for a return to in-person instruction. 

The Keystone campus will open for in-person instruction no later than Monday, March 15th 

Please complete the return to in-person instruction form to indicate your choice of in-person or continued distance learning by Wednesday, February 24th. Meetings will be held prior to returning for: 1) Parents of students returning to campus for the first time and 2) Parents of continued Upper Elementary distance learners. Meeting details will be shared at the conclusion of the parent survey. The Keystone mitigation plan is currently being reviewed to ensure it includes the most up to date information from the CDC and local health officials regarding in-person instruction. 

Should the AZDHS school benchmarks return to recommended hybrid delivery model for Maricopa County when released on Thursday, February 25th, Keystone will open campus for in-person instruction on March 1st. Should that decision be made, an immediate communication will be shared with our families. 

Thank you for completing the return to in-person instruction form, and for your continued support. As we prepare for a return to campus, please watch for additional communications related to our return to in-person instruction. 

In Health and Peace, 

Laura Hertzler
Head of School

*You may view the 2/18/21 Board Presentation by CLICKING HERE


February 12, 2021

Dear Parents of Charter Students,

Thank you for completing the return to in-person instruction parent survey. We will be releasing the data collected in conjunction with our upcoming board meeting on Thursday, February 18th. Following the board meeting, we will send the results to our community to so you may see the gathered data.

Keystone staff are in the process of receiving their vaccinations. We are also updating our Mitigation Plan with updated guidelines from AZDHS and the CDC, and we will be reviewing the most recent COVID-19 data for Maricopa County provided by AZDHS on Thursday, as well. All of these variables are being taken into consideration as we review a timeline for a return to in-person learning. We will continue to keep you apprised in the coming days as new information becomes available.


Laura Hertzler
Head of School


January 28, 2021

The Keystone Montessori Mission:

To inspire in children a passion for a lifelong love of learning in an environment which nurtures independence, creativity, confidence and tolerance while developing a sense of responsibility for self and community based on the principles and philosophy of Dr. Maria Montessori.


Dear Keystone Families,

Throughout the COVID-19 pandemic, Keystone’s mission has remained unchanged. Our work to inspire in our students a passion and lifelong love of learning is the cornerstone of all we do. Over the last eleven months we have faced significant challenges in the necessary transition to distance learning, and through it all, our staff remains steadfast in the commitment to keeping our community safe by following the guidelines of state and local health officials. Above all else, throughout this ongoing health crisis, we have harnessed incredible strength from your continued support and dedication to our school community.

While current COVID-19 metrics are currently in the substantial spread category and virtual learning remains the recommended platform, the arrival of the COVID-19 vaccine and the prioritization of teachers and school staff to receive the vaccine is a new factor that must now be considered. The Keystone Administration and Board of Directors continue to work together to monitor the data and are reviewing the Keystone safety protocols and Mitigation Plan currently in place. As we strive to return to in-person instruction, it is imperative that these protocols are aligned with any updates to the guidelines issued by the CDC and state and local health departments. CONTINUE READING



January 14, 2021

Dear Keystone Families,

We are pleased to share that Arizona has moved into Phase 1B of vaccine scheduling. As you may know, Phase 1B includes people working in educational settings. We have provided all necessary information to every member of the Keystone staff and will continue to support them in every way possible.

The benchmarks for Maricopa County remain in the substantial transmission category, and it is recommended that schools remain in virtual learning models. You may view the school benchmark data dashboard here. We will continue to monitor the benchmarks and keep you informed of any changes.

There are many exciting things coming up for our Keystone community. Please mark your calendars for the following events:

  • January 19th at 6:00pm will be our first Community and Classroom meeting of the new year! Please RSVP through School Cues.
  • The Montessori Journey will be held virtually on Saturday, January 30th. Invitations and additional information will be sent out soon.

We are excited to reintroduce our popular parenting program, Coffee Talk! We would like to host Coffee Talk once a month as a way for us to connect and discuss Montessori topics with our families. Please take a moment to share your thoughts so we may better serve you by completing this quick survey.

Progress reports will be distributed via email on January 15th – 22nd. Please reach out to your child’s Guide if you have any questions or concerns. We appreciate your continued support. The Keystone community is an inspiration during this challenging time.

In Health and Peace,

Laura Hertzler
Head of School
Keystone Montessori


December 28, 2020

Dear Keystone Families,

We hope you are enjoying a restful winter break. The time spent away from the hustle and bustle of our regular routines allows us to recharge and enjoy our families. As we begin to look forward to the new year and the hope and promise it brings, we would like to share some updates for our return on January 4th.

As you know, we watch the COVID metrics as the Arizona Department of Public Health (AZDHS) updates them each week. Currently the benchmarks in Maricopa County are still trending upwards. Each of the three benchmarks are in the red or substantial transmission category and AZDHS recommendations are for schools to be in a fully distance learning model. You may view the dashboard HERE. The number of cases per 100,00 is 576, the percent positivity is 17.5%, and hospital visits for COVID-like illness is 12.4% as of December 6th. In the best interests of our students, families, and staff, the Keystone Charter program will remain in a distance-learning model when we return from Winter Break on January 4th.

We remain hopeful the metrics will return to safe levels soon. When that day arrives, we will joyfully celebrate the children’s return to campus! As updates become available, we will continue to communicate any changes. It is our hope the New Year will bring healing and health to our community and we are continually grateful for your support and understanding.

In Health and Peace, 

Laura Hertzler
Head of School
Keystone Montessori


December 4, 2020

Dear Toddler and Children's House Parents, 

The safety of our students and staff continues to inform each decision made at Keystone. As changes are issued by the Arizona Department of Health Services, we review our policies and procedures on campus in order to ensure we are responding to updated recommendations and requirements. 

Keystone’s mitigation plan, which was drafted in compliance with Executive Order 51, requires that all students and staff wear cloth face coverings while on campus except during designated mask breaks and when outdoors where social distancing can be maintained.  The Governor’s mandate was initially for students over age 5.  Just before Thanksgiving Break, the Arizona Department of Health issued an Emergency Measure lowering the age at which students are required to wear cloth face coverings at school to 2 years old.  Therefore, Keystone has modified its mitigation plan to reflect the new mandate.  The Emergency Order continues to include an exception for students who can maintain social distance and to allow for mask breaks in a safe environment.  

You may review the updated face covering policy. The new protocols will be effective as of Tuesday, December 9th. Every effort will be made to ensure the children’s comfort and allow for safe mask breaks as needed. For our students in the Agaves toddler community, please refer to the face covering recommended by Ms. Lidia listed in the face covering policy if your child is age 2 or above. 

Thank you for your continued support and partnership as we work together keeping our Keystone community safe. 

In Health and Peace, 

Laura Hertzler
Head of School
Keystone Montessori


November 20, 2020

Dear Keystone Families, 

As Thanksgiving approaches, we would like to extend our thanks and gratitude to our families, students, and staff. During this time of challenge, we appreciate your open communication and ability to share your feelings with us. We thank each of you for your support of the mitigation plan and our efforts to keep the students on campus.  

The Keystone Board of Directors and Administration met on November 19th to review and discuss the COVID-19 benchmarks and data provided by the Arizona Department of Health Services (ADHS). 

Based on these guidelines, Maricopa County’s current metrics, and guidance from Maricopa County Department of Public Health, Keystone’s elementary and adolescent programs will return to Distance Learning beginning on Monday, November 30th.

Distance Learning will continue until the ADHS benchmarks return to recommended levels for a safe return to in-person instruction. You may view the ADHS benchmarks and dashboard here: https://www.azdhs.gov/preparedness/epidemiology-disease-control/infectious-disease-epidemiology/index.php#novel-coronavirus-schools and the document for a safe return for in-person instruction can be found here: Safely Returning to In-Person Instruction.



November 19, 2020

Dear Keystone Parent/Guardian,

In keeping with Keystone Montessori’s response plan for COVID-19, this letter is to inform you that we have had two positive test results for COVID-19 from individuals who were last present on our campus on Friday, November 13th and Monday, November 16th.  Due to privacy requirements, we will not be releasing the names of the individuals or details that may identify him or her. We are keeping them in our thoughts and wish them a full and speedy recovery.

In accordance with local and state regulations, we have reported the cases to local health officials, and any individuals determined to have been in close contact with the infected individuals have been contacted. All areas on campus where the person is confirmed to have been, will be thoroughly cleaned and disinfected according to all recommended procedures. We will continue to keep you informed of any updates or changes to the situation.

We do not have reason to believe that those who were not in close contact with the infected individual have reason to be concerned, but we ask that you, as always, watch for symptoms of COVID-19. 

Any of the following symptoms indicate a possible COVID-19 infection:

Temperature of 100.4 degrees Fahrenheit or higher when taken by mouth;
Sore throat;
New uncontrolled cough that causes difficulty breathing (or, for students with a chronic allergic/asthmatic cough, a change in their cough from baseline);
Diarrhea, vomiting, or abdominal pain; or
New onset of severe headache, especially with a fever. 

If you or any member of your family does begin experiencing any of these symptoms, we encourage you to contact your physician. If you would like information on COVID-19 testing, please visit https://www.azdhs.gov/index.php. We also ask anyone in the Keystone community who has tested positive for COVID-19 to please notify us by contacting Sue Smith at 480-460-7312.

If you have any questions or concerns, please reach out to Keystone Administration.

Thank you for your continued support and your patience as we navigate through this together.


Keystone Montessori


November 17, 2020

Community Meeting Presentation


November 12, 2020

Dear Keystone Families,

We are writing today to share information on the benchmark status from the Arizona Department of Health Services (ADHS). As you know, Keystone’s mitigation plan is formulated with guidance from ADHS and each decision we make is for the health and safety of our students and staff.   

The Keystone Administration monitors the COVID-19 metrics daily. We have observed a rise in numbers that make up the benchmarks for the Safe Reopening of Schools. ADHS advises that when a county has one benchmark in the red category for two or more weeks, even if different benchmarks, schools should consult with their local health department to determine whether to prepare to transition back to virtual learning with onsite support services. The most recent metrics show the number of cases has been in the red two weeks in a row, most recently with 129 cases per 100,000. At the time of our return to In-Person learning on September 14th, ADHS reported 52 cases per 100,000. Since that time, the number of cases has more than doubled and is still increasing along with the percent positivity rate. We have put in a formal request for a conference call with the Maricopa County Health Department and are waiting for their reply.

You can view the dashboard and current benchmark numbers HERE. In an effort to provide as much notice as possible, we want to make you aware that we are considering, in the best interest of our students and staff, to return to Distance Learning for our Charter students if this trend continues. We will be discussing this information with the Board of Directors before any decision is made.

The Toddler and Children’s House programs will remain open following all current safety protocols unless otherwise directed by the Governor. These programs are considered child-care by the State of Arizona. Keystone opened these programs in July and was mandated by Executive Order to keep them open and operational. Keystone will continue to follow all directives from state and local officials in our goal to keep our students and staff safe and healthy.

If we move to Distance Learning for all Charter students, it is our hope that the numbers will quickly fall to a safe level and we will return to In-Person instruction as soon as possible. We will make every effort to communicate any changes in a timely manner. Thank you for your understanding and continued support. 

In Health and Peace,

Laura Hertzler          Stefan Linder
Head of School        Associate Head of School


October 19, 2020

Please review our updated Mitigation Plan


October 12, 2020

In the event you need to have a COVID test we wanted to share some helpful information. ADHS has partnered with Arizona State University to launch several testing sites providing free saliva diagnostic testing for COVID-19. The tests are by appointment only with no walk-ins accepted. Children under 5 years old cannot receive saliva tests. For more information, please click HERE.


September 22, 2020

Community Meeting Presentation


September 10, 2020

Dear Keystone Families,

Please find the presentation from our first In Person Instruction meeting HERE


September 5, 2020

Dear Parents of Elementary & Adolescent Students,

The Board of Directors met on Friday, September 4th to discuss the AZDHS benchmarks as of September 3rd. The Keystone Administration is pleased to announce that the benchmarks have been met for a return to in-person instruction in the hybrid model! We are grateful for your support as we began our school year in a Distance Learning format to ensure the safety of our students and staff. Please take the time to read this communication in its entirety, as it contains important information on the procedures and timeline for a return to campus. CONTINUE READING


August 29, 2020

Dear Keystone Families,

Thank you for your continued support as we work together for the Keystone community. On Wednesday, August 26th, the Keystone Board of Directors met to discuss the reopening for in-person learning at Keystone.

The Keystone Board of Directors and Administration remains committed to the well being of our students, staff and families. As previously discussed at the August 10th Board of Directors meeting and subsequently communicated to the community of August 12th, we will continue to follow and refer to the Arizona Department of Health Services (AZDHS) benchmarks for determining a date for a safe return to in-person instruction for our Elementary and Adolescent programs. A link to the benchmarks and current metrics, which are updated every Thursday, can be found HERE

The full document outlining safely returning to in-person instruction released by the AZDHS can be found HERE


August 12, 2020

Dear Keystone Families,

We hope this letter finds you healthy and settled into new routines for the start of our school year. Each member of the Keystone staff appreciates your unwavering and continued support, patience, and kindness. In an effort to keep you informed on discussions and decisions for Keystone, we would like to share the most recent updates concerning COVID-19 and the Keystone community. CONTINUE READING.


July 25, 2020

Dear Keystone Families, 

Please find our updated Safety Protocols HERE. Thank you for your continued support and we look forward to seeing you soon.


July 18, 2020

Dear Elementary and Adolescent Parents,

As we approach our first day of school, we would like to thank you for your messages of support. The staff and administration have worked throughout summer to ensure the best possible beginning to the year online. In order to properly prepare for the start of the year, please take note of the information below. CONTINUE READING  


July 15, 2020

Dear Toddler and Children’s House Families,

As we approach our first day back to campus for the 2020/2021 school year, we would like to thank you for your messages of support and your patience as we planned for the start of school. The Staff and Administration have worked all summer to ensure a safe return to campus for our students, and we are so eager to see the children! CONTINUE READING


July 3, 2020

Dear Elementary and Adolescent Parents,

Thank you for taking the time to review our safety protocols and completing the survey regarding our return to campus for the 2020-21 school year.  CONTINUE READING


June 25, 2020

Dear Keystone Families, 

All of us here at Keystone Montessori are looking forward to receiving the students back onto campus and have been busily working to welcome them for the 2020-21 school year! The guidelines that were put forth by the AZ Department of Education were extensive. The Keystone staff and administration spent countless hours looking at each recommendation, weighing it against our Montessori principles, and working together to design a plan that will address the safety of our community. CONTINUE READING


June 3, 2020

Dear Keystone Families, 

We are pleased to share an update regarding the reopening of Keystone Montessori School. Your support and understanding through the end of the school year has been a source of strength for each of us, and we are looking forward to welcoming the children back to campus. CONTINUE READING



May 16, 2020

Dear Keystone Families,

We are so grateful for your continued support throughout the end of this unusual school year. The Keystone community has been a constant source of inspiration for the staff with your messages, updates, and your participation in all of the Learning from Home activities! CONTINUE READING



April 3, 2020

On March 30th, Gov. Ducey and Supt. Hoffman jointly announced physical school closures through the end of the school year. While the Keystone Staff is saddened by this development, we support the need to ensure the safety of our students and families. Every member of the Keystone staff is working to support our students remotely and we will continue to do everything in our power to keep our community connected and learning. 



March 29, 2020

Dear Keystone Families,

The Keystone Board of Directors continues to be grateful for your support and understanding during this uncertain time. We would like to acknowledge the time and effort each member of the Keystone staff has poured into supporting the children as Learning from Home continues. We also acknowledge your efforts in integrating educational activities into your homes and schedules. CONTINUE READING



March 25, 2020

Dear Keystone Families, 

What a week! It has been both very busy and much too quiet on campus. The staff has been in and out as they prepare lessons for Learning from Home and my heart is full seeing them even if it is for just a short time each day. We are diligently keeping our social distance while we work! The highlight of the week was overhearing some of the first Zoom meetings. The sound of the children talking, laughing, and sharing brought some joy to campus.  Thank you for your continued support this week.  Please find some updated information below! CONTINUE READING



March 20, 2020

Dear Keystone Families,  

We would like to thank you for the outpouring of support the office has received in the past week. The Keystone Board of Directors deeply appreciates your patience, understanding, and flexibility.  CONTINUE READING



March 17, 2020

Dear Keystone Families,

On Monday, March 16th the Keystone Faculty, Staff, and Administration gathered together to discuss how to best support each other, our families, and our students in the coming weeks.  The time we spent together solidified what we already knew about our Keystone Family. We are committed to our students with the whole of our hearts and we will do everything we can to continue to support each and everyone of them while we navigate these uncertain times ahead. CONTINUE READING



March 15, 2020

Dear Keystone Community,

As we continue to navigate the COVID-19 spread, our goal remains the same - honest, open, and transparent communication with every member of our community and the continued care of each Keystone student.  Please rest assured that each decision of the Keystone Administration and the Board of Directors is made with the best interest of our students and the entire community in mind. CONTINUE READING



March 13, 2020 

Dear Keystone Community,

Pending Board approval, we have made the decision to close Keystone Montessori beginning Monday, March 16th through at least Friday, March 20th due to COVID-19 national and state emergencies that have been declared. CONTINUE READING

Additional resources

Provided by the Centers for Disease Control and Preventions:

Centers for Disease Control and Prevention

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