Rubuta ci gaba ga wannan sakin layi - Tennell ta lashe gasar farko lokacin da ta ke da shekaru goma. A shekara ta 2010, tana da shekaru 12, ta zo a matsayi na farko a yankin Upper Great Lakes, wanda ya cancanci ta shiga gasar matasa a 2010 U.S. Junior Nationals, inda ta zo a matsayi na 10. Manufofinta na kakar wasa mai zuwa shine don kammala ƙwallon ƙafa biyu da kuma dawowa zuwa Junior Nationals. A cikin 2011, ta zo a matsayi na uku a cikin rukunin matsakaici a Upper Great Lakes Regionals, da kuma na 15 a Gasar Junior ta Amurka, kuma a matsayin mai tsaka-tsaki. A cikin 2012, a matsayin mai farawa, ta zo a matsayi na uku a duka sassan Midwestern da 2012 Upper Great Lakes Regional. Ta yi gasa, kuma a matsayin sabon shiga, a gasar zakarun Amurka ta 2012
a San Jose, California, inda ta zo a matsayi na goma a gaba ɗaya, bayan samun maki 32.60 kuma ta zo a matsayi na goma a cikin gajeren shirinta da maki 68.78 a cikin kyautar ta kyauta. Daga baya ta gaya wa wani mai ba da rahoto cewa ta kusan rasa hanyar zuwa taron, kuma ta fara shirinta na gajeren lokaci a gefen da ba daidai ba na rink saboda shi ne karo na farko da ta yi wasa a cikin babban filin wasa kuma babu layi ko da'irar hockey a kan kankara kamar a kan rinks ta saba da.