Just ahead of the back-to-school season, Amazon plans to make a major foray into the education technology market for primary and secondary schools, a territory that Apple, Google and Microsoft have heavily staked out.

Monday morning, Amazon said that it would introduce an online marketplace with tens of thousands of free lesson plans, worksheets and other instructional materials for teachers in late August or early September.

Called Amazon Inspire, the education site has features that may seem familiar to frequent Amazon shoppers. Search bar at the top of the page? Check. User reviews? Check. Star ratings for each product? Check.

By starting out with a free resources service for teachers, Amazon is establishing a foothold that could expand into a one-stop shopping marketplace — not just for paid learning materials, but for schools’ wider academic and institutional software needs, said Tory Patterson, co-founder of Owl Ventures, a venture capital fund that invests in ed tech start-ups.