Their fourth outing was a free-scoring affair with only five wickets lost across the two innings.
Bay of Plenty set Northland 146 for victory which seemed like a tough task.
However, the combination of Templeton (75 not out) and Paige Whitten (53 not out) made it look like a cakewalk as they romped home with eight wickets left in the sheds.
Northland's last game didn't go to plan as Templeton's 31 wasn't enough. Northland made 100 for 7 before Hamilton chased it down with only two wickets lost.
Templeton was a standout throughout the competition, amassing 255 runs to lead all scorers.
The junior secondary schoolboys meanwhile are playing off for third and fourth against Counties-Manukau in their tournament at Owen Delaney Park in Taupo.
Northland started well with a 37-run win over an ND Invitational XI before being humbled by eight wickets against Hamilton.
Their third game, against Bay of Plenty Lakelands, was their most complete performance as they romped to a 10-wicket win.
After electing to bat, Lakelands immediately found themselves under pressure as Will Potter (2 for 11) led an early charge from the Northlanders.
Vincent von Mulert-Carvell came on when Lakelands were at 54 for 4 and brought about a quick demise.
He took five wickets for five runs in no time to end the innings at 65. Wicketkeeper Sam Lints took two catches and three stumpings in an impressive performance with the gloves.
Porter (32 not out) and Cole Jakicevich-Roberts (21 not out) got the job done without losing a wicket.
In their final group match, great bowling performances from Nathan Parkes (4 for 28) and Potter (3 for 47) couldn't halt Waikato Valley's charge as they beat Northland by 108 runs.
Northland then scored 184 in their first innings of their two-day playoff against Counties-Manukau.
Kian Bird led the way with a fighting 58 while getting small contributions from other batters.
