2009-10: Nanne skated in 26 games for Minnesota's Edina HS as a freshman as the Hornets captured the state AA championship. He scored 4 goals with 1 assist and was plus-four with 6 penalty minutes.
2010-11: Nanne skated in 27 games for Edina HS as a sophomore as the Hornets captured the Section 2AA title and competed in the state tournament. He scored 13 goals with 16 assists and was plus-10 with 12 penalty minutes. Edina defeated Burnsville in the Section 2AA final and defeated Blaine in its first State Tournament game before falling to Duluth East in the semifinals and Eagan in the third-place game. Nanne was selected to play in the High Performance U17 and Final 54 tournaments following the season.
2011-12: Nanne represented the USA at the 2011 Ivan Hlinka Tournament, played for Team Southwest in the Upper Midwest Elite League and represented Minnesota White in the Bauer NIT prior to his junior season at Edina HS. In four games at the Ivan Hlinka tournament he scored 1 goal with 2 assists and was minus-two. The USA won three of its four games yet finished fifth in the eight-team tournament. In 23 games for Team Southwest, including three playoff contests, he scored 7 goals with 13 assists and had 12 penalty minutes. In 28 games for Edina he scored 15 goals with 12 assists and was minus-one with 34 penalty minutes. Edina reached the Minnesota state tournament after winning the Section 2A championship and finished 20-5 after falling to Duluth East in a consolation game. Nanne committed to playing at the University of Minnesota in 2013-14 after spending a year in the BCHL with the Penticton Vees. Ranked 188th amongst North American skaters in Central Scouting's final rankings prior to the 2012 NHL Draft, he was selected by Minnesota in the 7th round (188th overall).