Oldham won in slopestyle at the Nor-Am Cup in Calgary in February 2018 and took third place in slopestyle at Le Relais the following month . At the beginning of the 2018/19 season she started the World Cup for the first time in Stubai and finished 19th in slopestyle. As the season progressed, she came second in slopestyle on the Alpe di Siusi and third in Mammoth . She also won the Aspen / Snowmass Open in Aspen and took her first World Cup victory in Slopestyle in Silvaplana . She won the Slopestyle World Cup and achieved tenth place in both the overall World Cup and the Big Air World Cup. At the 2019 Junior World Championships in Kläppen , she won the silver medal in Big Air. She also finished ninth there in Slopestyle. The following year she finished sixth in slopestyle and fifth in big air at the Winter X Games in Aspen and won the gold medal in big air at the X Games Norway .