The large fields, including many unknown athletes, are difficult to predict even though past results and current rankings are a good guide. Success at this level requires athletes performing at their best on the day of competition and, as in the past, the form book is only a guide.
Harry Symes goes in ranked in both 200m and 400m. He has chosen the one-lap race with its more demanding programme. He has the ability to be amongst the leaders and go under 49 seconds for the first time. He still has a year at school to beat his brother's Collegiate record. Last year he ran in the winning 4 x 100m and 4 x 400m teams and is key runner in both this year. While retaining the titles might be hard, the teams have the ability to be in the top half of their respective finals.
Jane Lennox has moved into third place in the steeplechase with her performance in Palmerston North 10 days ago. Lennox has made real technical improvements and although she has the road race early in the day has both the talent and determination to make her mark near the front of both the steeples and road race field.
Grace Godfrey is a key member of the strong Collegiate School junior girls relay teams. Both the 4 x 100m and 4 x 400m have produced times that would have won a medal last year and are strong contenders. But they know this is 2015 and it all depends on how they handle the pressure when it matters. Godfrey has also moved into the rankings in the individual 400m and could make some impact.
Collegiate Club Captain Roimata Hipango won the North Island Schools senior girls triple jump in April and is now beginning to come close to the 11.30m jump produced in Auckland.
She also has a key role to play on the final bend in the 4 x 100m relay. Hipango is an athlete that thrives on competition and the triple jump could be a tight and enthralling competition.
Collegiate field a strong road race team in the Year 9 girls. Caitlyn Alabaster, Sophie Redmayne and Libby Abbott won the cross country team title back in June and hope to repeat the performance on the roads around Caroline Bay.
Opetini Dryden as a Year 11 athlete has his first taste of senior competition in the javelin. Dryden took bronze in the junior ranks last year and is showing a consistency of performance over this new season. A medal is a big ask for a young thrower but he has the potential to be in the mix in the seniors.
As always there will be new faces and new medal winners. Junior performances are unpredictable and especially hard to forecast.
Young Oliver O'Leary only stepped up to 800m three weeks ago and has set substantial personal bests in both races he has competed in.
At club night on Tuesday in beautiful still conditions he ran an outstanding 600m in 1:25.9 that indicates sub 2-minute potential.
He goes in as an unknown but could well turn a few heads in Timaru. The best thing is he is unknown and goes in without the attendant pressure others may feel.
He also runs in the 4 x 400m and 4 x 100m relays.
New Zealand School Championships are special events culminating in a series of finals on Sunday and a large group of Wanganui athletes hope to be part of that afternoon action.