To investigate performance of children with cerebral palsy (CP) at GMFCS Levels I-II on sports-focussed gross motor assessments; and concurrent validity of mainstream and CP-specific high-level assessment batteries and field tests. Fifty-four children (6-12 years) with CP at GMFCS I-II completed the Test of Gross Motor Development-second edition, Gross Motor Function Measure-Challenge Module, Muscle Power Sprint Test (MPST), 10 × 5 m Sprint Test (10 × 5 mST), Vertical Jump, Broad Jump, and Seated Throw. Correlations between measures, age and mobility level, and group differences between age and mobility level were examined and content analysis performed. Children at GMFCS I demonstrated significantly higher gross motor assessment battery scores than children at GMFCS II (U = 73.5-109.0, p < 0.001). Performance improved with age for children at Level I but not II. Children with higher overall motor scores scored higher on running (MPST, 10 × 5 mST, r = -0.516 to -0.816, p < 0.001), jumping (Vertical Jump, Broad Jump, r = 0.499-0.774, p < 0.001) and throwing (Seated Throw, r = 0.341-0.500, p = 0.012 < 0.001) field tests. High-level gross motor assessments were achievable and appropriately challenging for children with CP at GMFCS I-II. Scores discriminated between performance and were associated with mobility level. Concurrent validity was established between gross motor assessment batteries, and locomotor field tests.IMPLICATIONS FOR REHABILITATIONFor children with cerebral palsy at GMFCS I-II, sports-focussed assessments should be used to assess high-level gross motor function.The Gross Motor Function Measure-Challenge and Test of Gross Motor Development demonstrate no ceiling for children with cerebral palsy at GMFCS I-II.Single-item running and jumping field tests provide targeted skill assessment and estimate sports skills for children with cerebral palsy.