The 17-year-old looked like a seasoned pro as he received the ball on the left wing to fly past Hull's Jake Connor to score a try 45 seconds into his professional debut.
Castleford went on to lose the game 30-12 but much of the talk after the contest was still about the teenage sensation.
Video footage shows the youngster being mobbed by his schoolmates at Queen Ethelburga's Collegiate in York on Friday morning as he returned to class.
Qareqare was thrust into the starting line-up against Hull with the Tigers missing six players from their Challenge Cup semi-final win over Warrington Wolves.
The winger was quick to repay head coach Daryl Powell s show of faith in him and told Sky Sports after the fixture: "When he called me, it kind of felt like a dream.
"I was in maths class, the phone picked up and I had to pinch myself because it literally felt like a dream.
"Of course, it was a loss, but getting that try with my first touch of the game was brilliant - it's an out-of-this-world feeling. Having the crowd behind me as well was amazing."
Qareqare was presented his debut shirt by captain Michael Shenton in the dressing rooms before the game.
Head coach Powell added: "I'm made up for him. For a young bloke to make his debut and do that with his first touch, I thought that was a great moment.
"There was not a lot to cheer for us today, but that was worthy of getting on your feet. He is still at school, so he trains with us in the school holidays and at weekends."