Emma Titchener told the presenters that her school allowed pupils to change their footwear as they believed it made a huge impact on their productivity.
She explained: "Research concluded that it made a massive impact on pupil performance, so we trialled it and saw a massive difference and tried it for the rest of the year. It has made the children more calm."
But, Piers was not impressed as he asked: "What kind of message does it send to them? Where is the discipline that comes with this?"
Piers Morgan and Susanna Reid co-hosted today's edition of Good Morning Britain
Piers slammed Emma's argument that slippers would make pupils more productive
Emma hit back: "It's not about uniform, it's about learning. The children still come to school in uniform and dressed quite smart."
However, the journalist would not back down and insisted the idea that pupils should wear slippers was "ridiculous", commenting: "Kids should not be mollycoddled. What is wrong with us?"
The presenters were then shown the variety of footwear that the children in Emma's school were wearing, which infuriated the 51-year-old even more.
He said: "Go back! Where's the furry ones again… My daughter has the most outrageous slippers."
Good Morning Britain: The best bits
Wed, November 23, 2016
Good Morning Britain: The best bits of the morning TV show with Susanna Reid, Piers Morgan, Ben Shephard and Kate Garraway.
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Good Morning Britain's best bits
Susanna was forced to reign in Piers as he ranted at Emma
Stop, stop! Let her answer!
As he continued to argue that the footwear was outrageous and unacceptable in schools, Susanna was forced to step in and stop him from ranting so that Emma could defend her decision.
She demanded: "Stop, stop! Let her answer!" as she held her co-host back.
Adam Hills revealed he only appeared on the show because Susanna was presenting
He explained: "If this show was called Good Morning Britain with Piers Morgan, you'd never have any guests."
The brunette beauty sighed with relief: "Finally, we have established the real reason. We're no longer living in your world of delusion, Piers."
Good Morning Britain airs weekdays on ITV at 6am.