Tennell came in second place overall as a novice at the 2013 Midwestern Sectionals, coming in first place after the short program with 46.05 points and coming in fourth place after the free skate with 72.95 points. She won the gold medal at the Upper Great Lakes Regionals, also as a novice. She won the bronze medal, her first "notable medal", at the 2013 U.S. Nationals, again in the novice division, even though she had only two triples in her free skate. She opened her program with a triple Salchow, but fell while attempting a triple toe loop. She successfully executed three triple jumps, coming in fourth place in the free skate and earning 116.91 points overall. Tennell came in second place at the 2014 Midwestern Sectionals as a junior. She came in fourth place at the 2014 U.S. Nationals and second place at the Gardena Spring Trophy, again as a junior.