Second-graders in Bellevue were back in buildings and teachers resumed live virtual classes on Tuesday after a week of public feuding between the school district and union over in-person learning.

The Bellevue School District and its teachers union, the Bellevue Education Association, reached an agreement that allowed kindergartners through second-graders to return as the district previously planned, but with some additional protocols in place that neither side has discussed in detail. School was canceled for everyone on Monday as management and labor sought a resolution.

Early last week, the union had voted to halt live instruction to protest the district’s plan to expand in-person learning before all educators had access to a vaccine. On the first day second-graders showed up to school buildings, last Thursday, many students were taught by substitutes. The district filed a lawsuit in response, unsuccessfully seeking immediate court intervention on the grounds that the union’s actions constituted a breach of contract.

The battle in Bellevue, the largest school district in King County to expand in-person learning, is emblematic of the stress the virus has put on relationships among districts, unions and families.

“Although the tentative agreement resolves some key concerns, the process it took to reach the decision exposed deep hurt and distrust throughout our community,” Allison Snow, the union’s president, wrote in a statement late Monday. Snow said the union only narrowly agreed to resolve the dispute with the district.

According to releases from the district and union, the new agreement includes “health-based” triggers to delay the expansion of in-person instruction and clearer guidelines for documenting safety protocol violations. The district has also formed a vaccine planning committee to ensure educators have access to doses.

A hearing on the district’s lawsuit, which also seeks damages from the union because it needed to hire substitutes, is still scheduled for Thursday.