Some classroom field trips are expensive. Others, like a journey to Mars, are downright impossible.

But Google GOOGL has a solution. The tech giant will begin helping teachers use Google Cardboard, the company’s ultra-cheap virtual reality headsets, to take students on virtual tours to far-flung places.

Starting Monday, schools can apply for a visit from a Google team that will provide kits including Cardboard units for each student, a tablet for teachers and a specialized router. The program, called “Expeditions,” will offer virtual sojourns to more than 100 destinations, from undersea reefs to the Great Wall of China.

Google developed the educational content in partnership with organizations like PBS, Houghton Mifflin Harcourt, the Planetary Society, the Wildlife Conservation Society, and The Starfish Foundation.

Classrooms won’t be able to keep the virtual reality kits — Google says they’re a loan, though free of charge. The company plans to start with schools in six U.S. states, including California, Illinois, New York, New Jersey, Connecticut, Texas). It will also work with educators in Brazil, Australia, New Zealand, and the U.K.

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