Luke Shaw, 18, Raheem Sterling, 19, and Ross Barkley, 20, are among those under 21 who could earn a place in England's squad for Brazil.
But former England Under-21s coach Pearce, who will take over at Nottingham Forest in July, said there was no point taking youth if they would spend most of their time on the bench.
"There is a Toulon tournament this year as well as an under-21 qualifier against Wales in August – I'd most certainly involve Luke (Shaw) in both of those before taking him to a World Cup," Pearce said.
"I'd like to make sure younger players stay in their age-groups a little bit more and actually play.
"The most important thing is that the best young players in the country play - at whatever age group.
"Being in the senior squad and not playing isn't helpful."
