President Nicolas Maduro's government has delayed the restart of in-person classes several times, amid new peaks in infections and vaccination delays.
Youth Minister Mervin Maldonado said 8.7 million children would return to classrooms across the country and some 3.1 million students would resume attending universities.
Children dressed in uniforms of blue pants and red shirts and wearing masks filed into schools in the capital Caracas starting at 7 am, as teachers dispensed antibacterial gel.
One mother, Jenny Bejarano, said she felt "a bit nervous" about potential coronavirus infections as she dropped off her son Fabian at the Venezuela Experimental Education Unit school in central Caracas.
"Our health system, it's not a secret from anyone, is lacking," said Bejarano, a cardiorespiratory staffer at a private clinic. She said there is a deep scarcity of medications and supplies.
But 8-year-old Fabian was excited to see his third-grade classmates, said Bejarano, 47.
About 40% of the school's 1,700 registered students returned to classes on Monday, said community representative Pedro Zambrano.
"For us the return to classes is important, but we have doubts," said Maria Clemente, an official at the Venezuelan Federation of Teachers, which has some 325,000 members.
Some teachers will remain absent for fear of getting sick or because of low salaries, she said, adding that the maximum monthly salary for her members is 118 bolivares, equivalent to $27.
Down the road at Caracas' oldest school, the Andres Bello Educational Complex, Director Wilmer Marcano presided over a mostly empty building. Repairs will delay its restart for two weeks, he said.
Those age 12 and up in Venezuela are now eligible for their first dose of a COVID-19 vaccine.
The government says 56% of the population of 28.7 million has been vaccinated, though the Pan-American Health Organization says just 21.6% are fully protected.