This study evaluates the R3THA™ technology-supported assessment protocol for home-based rehabilitation in children with cerebral palsy (CP). It focuses on the reliability and validity of R3THA™ in assessing hand and arm function, comparing kinematic assessments with standard clinical assessments. Conducted during a 4-week summer camp, the study involved children with CP aged 3-18, assessing their functional and impairment levels. The findings suggest that R3THA™ is more reliable for children aged 8 and older, indicating that age significantly influences the protocol's effectiveness. Results also showed that R3THA-AP's kinematic measurements of hand and wrist movements were positively correlated with the Box and Blocks Test Index (BBTI), reflecting hand function and dexterity. Additionally, R3THA-AP's accuracy metrics for hand and wrist activities aligned with the Melbourne Assessment 2's Range of Motion (MA2-ROM) scores, suggesting a meaningful relationship between R3THA-AP data and clinical assessments of motor skills. However, no significant correlations were observed between R3THA-AP and MA2's accuracy and dexterity measures, indicating areas for further research. These findings validate R3THA-AP's utility in assessing motor abilities in CP, supporting its integration into clinical practice.