Harry met pupils at Ninestiles, an academy in Birmingham, to mark the launch of an Invictus Games education scheme called Inspire.
Dressed casually in a dark polo shirt and jeans, Harry seemed at ease as he dived for shots while playing with pupils and answered youngsters' questions.
Playing several rallies against children in Year 7 and Year 11, Harry joked his back was in pain after reaching for a low shot - and cried out "nice" when one of the players won a point.
During a question-and-answer session with the children, the duke of Sussex was asked by a pupil to name someone who inspired him.
Harry replied: "It's not a single person, it's a whole group of people. And it's not always the people you probably think it is."
Pointing to the Invictus Games competitors, he said: "It's these guys. This Invictus community of people who get knocked down but keep getting back up."
It comes after the duke made his first public appearance since returning to the United Kingdom, when he attended an event for the Invictus Games on Thursday evening, describing life since his return as "eventful".
Speaking at the event, Harry declared: "It's wonderful to be back on British soil."
The duke's public engagements came as the serialisation of a book about his mother Diana written by his uncle Earl Spencer continued to make serious allegations against King Charles.
In an extract of an interview with the BBC published on Friday evening, Harry's uncle insisted he is "telling the truth" over the explosive allegation Charles said "we'll forget her soon enough" in the days after Diana's death.
The earl said: "(The King) went ballistic, would be the right term, and started really going for my family as a whole, about their sense of duty, not being adequate enough, and ranted for a while, I have no idea how long, but it was a significant period, and I just listened.
"And then he stopped, and I thought, 'Oh now he's going to pull himself together and say something more appropriate', and then he said, 'We'll forget her soon enough'."
The comments made by the earl in a new memoir of his sister prompted an unusually robust response from Buckingham Palace, which said "the pain of fraternal grief can cloud reason".
25°C