The 2021 season for the California ProKart Challenge came to a close over the October 2-3 weekend with the sixth and final round of the year held at the CalSpeed Karting facility. It was the second visit to the Fontana, California facility in 2021, previously hosting the double-header weekend in June. For the series finale, the near 100 Superkarts! USA regional entries took to the ‘Classico’ layout to decide this year’s series champions.
 

The California ProKart Challenge hosted the penultimate round of the 2021 season on the September 11-12 weekend at the Willow Springs International Raceway. The Rosamond, California facility has been the site of many Superkarts! USA regional program events in the past, including both the famed Streets of Willow course and the karting circuit. The two-day event for Round Five of the 2021 championship program was held on the nine-turn, 6/10-mile kart track in the counter-clockwise direction.