Sophie Winkleman has revealed she has pulled her children out of school twice, because they were going to be given iPads to use.
Lady Frederick Windsor, who is married to the son of the late Queen's cousin, had serious concerns when she discovered her kids would be using the electronic devices to help with their education.
The actress, best known for playing Peep Show character Big Suze, objected to children being given iPads from the age of six and "immediately started looking for different schools".
Winkleman has two daughters with her husband, Lord Frederick Windsor, and fears how the use of screens and online learning is becoming "normalised".
She took daughters, Maud, 9, and Isabella, 7, out of £20,000-a-year Thomas's Battersea - the school which their royal cousins Prince George and Princess Charlotte previously attended.
Sophie, who is also Strictly host Claudia Winkleman's half-sister, believes that the use of tech and addictive social media apps is affecting learning and making teenagers depressed.
She said that pupils at schools attended by her children "were going to be given tablets, all of them from Year One [aged 5/6] to Year 6 [aged 10/11]... And this was announced in a proud - is this not exciting? - way and I immediately started looking for different schools. I have moved them twice now to get them out of tech-heavy schools."
While praising St Thomas's for being happy and energetic, Winkleman said the school did not suit her daughters.
Her daughter, Maud, started both at the Battersea school on the same day as Prince George in September 2017.
The internet is a toxic wilderness we're letting children stumble through without protection," she told The Sunday Times.
"I think many UK schools have swallowed the push for more digital learning partly because of pressure from parents, who think if their child is learning online at seven they will be the next Bill Gates. I lived in California and spent time with bigwigs in Silicon Valley and tellingly they did not let their children near screens."
The royal said she is "thrilled" at the launch of a campaign for greater regulation of smartphones by parent group Us for Them.
The Safe Screens campaign is calling for the Government to ban smartphones completely for under-16s and bring in "tobacco-style health warnings" on all smartphone packaging.
It's been backed by head teachers the former social mobility tsar, MPs and some behaviour experts.
Some studies have suggested links between pre-schoolers' screen time and difficulties with attention - but there is by no means consensus among the research community that such a relationship exists.
Winkleman, whose eldest daughter is allowed to use a tablet for a limited period on Sundays, added that she wanted her kids to read books and "to focus and to learn to think deeply"
Her children are very close in age to the Prince and Princess of Wales' kids - and Sophie has spoken in detail about her daughter Maud's close bond with Prince George.
In an interview with Hello , she said: "We were invited to tea at Kensington Palace just before Princess Charlotte was born.
"Maud and George got on very well… He is a very clever, articulate little boy and was speaking long before other toddlers his age."
The actress wed Lord Frederick, a financial analyst, at Hampton Court Palace in 2009 before going on to have their two children.
Lord Freddie is the son of Prince Michael of Kent, who is the Queen's cousin as his father, Prince George, was the younger brother of Edward VIII and George VI.
Sophie was seen sitting beside senior members of the Royal Family during a vigil at the late Queen's coffin and attended her funeral at Westminster Abbey last September.
The actress has previously said she was welcomed into the clan with open arms, particularly by the Queen and King Charles.
Speaking to The Times, she said: "I've been incredibly welcomed with open arms by all of them... They'd never tell me off at all if I wanted to play some [racy] role."
Following their wedding, the couple moved to the US so that Sophie could further pursue her acting career and Maud was born while they were living in California
The couple later moved back to the UK and welcomed their second daughter, Isabella, back in 2016.
