About 40 Palo Alto school administrators were called to district headquarters this afternoon to sign a letter retracting a previous document they submitted to Superintendent Mary Frances Callan, which threatened the establishment of a union if working conditions didn't improve, according to sources within the district.

It is unknown at this time whether the administrators signed the retraction letter.

The administrators are a part of the district's Management Team, which includes principals, assistant principals, and district office coordinators.

The group sent a document Sept. 6 to Callan that cited "a lack of trust and productive communication between the ... Management Team and the Superintendent and her Senior Cabinet."

Members of the district's Board of Education obtained a copy of the document soon after it was sent to Callan.

The board will hold an emergency closed session meeting at 7 a.m. Sunday at the district's headquarters to discuss the situation.

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