The government's offer of free technical support to help schools access Google and Microsoft's education platforms is "restrictive", heads have said.
The Department for Education has said that "thousands of schools" will benefit from its £14 million investment in expert help for staff to get set up on G Suite for Education or Microsoft’s Office 365 Education.
But school leaders have said the DfE should "bear in mind that there are many different providers out there", and called for the programme to be extended "to provide more general support which is not confined to two companies".
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Early indications from Tes research suggest that, while Google and Microsoft have the lion's share of the market, schools use a wide range of platforms to deliver online learning.
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Of more than 3,000 educators who have so far responded to a Tes poll, 10.7 per cent said their school's primary platform for distance teaching is Purple Mash, while 3.5 per cent said they use Tapestry.
Geoff Barton, general secretary of the Association of School and College Leaders, told Tes: "Any technical support for schools at this extremely challenging time is a good thing, but the government does need to bear in mind that there are many different providers out there, and that to focus on Google and Microsoft does seem rather restrictive.
"We appreciate this is all being done at pace but it would be good to see this programme extended as time goes on to provide more general support which is not confined to two companies."
The technical support for schools is part of a £100 million package to improve access to remote learning amid the coronavirus crisis.
Liz Sproat, Google's head of education for Europe, the Middle East and Africa, said last week: "This is a challenging time for UK schools, educators, parents and students, and this initiative by the Department for Education provides vital support to schools seeking to enable remote learning.
"We are delighted that our suite of tools, resources and our partners can help schools maintain learning during these difficult times."
Cindy Rose, chief executive officer at Microsoft UK, added: "Schools across the UK are facing unprecedented challenges as their staff demonstrate incredible resilience, imagination and passion to ensure children are safe and able to keep learning while at home.
"We’re proudly working with the Department for Education to support the roll-out of remote learning technology to those who need it."
The DfE has been approached for comment.