Lamont said schools will also be required to continue providing to-go meals to children under the school lunch and breakfast programs. He was expected to sign a new executive order later in the day.
Lamont said he is working with state and local education officials to determine whether summer school programs should be held. More details are expected later this month.
The governor and his education and early childhood commissioners will provide more information about Tuesday's decision at an afternoon briefing.
"I know how important it is for so many students and teachers to finish out the school year, and I was holding out hope - particularly for high school seniors - that we'd at least be able to complete the final few weeks, but given the current circumstances and to protect everyone's safety, it has become clear that it's just not possible," Lamont said in a written statement.
The state's largest teachers union, the Connecticut Education Association, praised Lamont's decision. The union understands "the emotion and sadness regarding closing schools and missing certain milestones and celebrations" but protecting the health of students and staff should be the top priority, CEA President Jeff Leake said.
Meanwhile, Lamont said efforts are still underway to distribute remote learning resources, including 60,000 Dell laptops and 185,000 Scholastic book packs. They've been arriving in waves because of the global supply chain shortages due to the COVID-19 pandemic.
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