His message to the All Blacks: "Kia Kaha, stay proud, stay strong and don't forget your lucky Tradies underwear."
Oscar said he is incredibly excited.
"I have never been out of the country and have had to get a passport. I keep saying to Mum, I can't believe we're going to Japan."
The excitement has extended to Oscar getting a stack of books on Tokyo and Japan from the Te Awamutu Library.
"I've been reading up about Tokyo and sights to see and learning some of the basic Japanese phrases, like thank you, excuse me, please, hello and goodbye," Oscar said.
Pirongia School principal Jan Cullen said it couldn't have happened to a nicer family.
"Oscar is a lovely shy kid, the trip will certainly be the makings of him.
"I jokingly said to him, 'don't take your mother, take me'. I went to the 2007 World Cup in France and would love to go to another one."
Jan said Oscar had mentioned he was scared about running out onto Yokohama Stadium in front of a sell-out crowd.
"I told him not to worry because all of Pirongia will be watching and right behind you."
Oscar's prize pack includes airfares, four nights' accommodation, tickets to the All Blacks opening World Cup game against South Africa, food and beverages.
The youngster and his mum have extended their stay in Tokyo to eight nights.
They will only get to the one rugby game but have planned lots of other activities in Japan's capital city.
"It's great to have Mum coming with me, she made the video and always watches the All Blacks with me."
Kylie found out about the competition win three weeks ago, just before the school holidays.
"I had to keep it a secret for two days before Oscar found out at the schools' Gymsports at the Trust Waikato Te Awamutu Events Centre.
"He had no idea until Seven Sharp host Jeremy Wells, decked out in a Japanese sumo wrestling suit, entered the Events Centre asking for an Oscar Parker before announcing him as the lucky competition winner."