This dataset contains de-identified full-body three-dimensional motion-capture and ground reaction force records collected from 43 children and adolescents during a multi-task laboratory movement assessment. The public release includes 4604 C3D files, 4603 tab-delimited force-platform files, and 4601 paired C3D-force trials. Data are organized by anonymous participant identifiers and accompanied by trial-level metadata, task-label harmonization tables, marker-label documentation, quality-control reports, manuscript support tables, and scripts for regenerating the manifest and QC summaries. The task battery includes static calibration, range-of-motion movements, Functional Movement Screen tasks, Adams forward-bend testing, sit-to-stand, walking, running, obstacle crossing at nominal 15%, 30%, and 45% conditions, vertical jump, single-leg hop, single-leg squat, drop jump, and simulated abnormal-gait conditions. C3D headers report a 90 Hz motion-capture sampling rate. Force files report a 450 Hz force sampling rate and two force plates. Users should begin analyses from paper_assets/metadata/trial_manifest.csv. For synchronized kinematic-kinetic analyses, use only trials with pair_status = paired. Unpaired C3D-only and force-only records are retained in the release and documented in the QC reports, but should be excluded from analyses requiring synchronized C3D-force data. Nonstandard C3D point counts are documented as marker-label/export variants; users should harmonize markers by label rather than by point index. The public package contains only anonymous subject IDs, de-identified C3D and force-platform files, approved summary metadata, QC documentation, manuscript tables, and reproducibility scripts. Direct identifiers, consent forms, subject-name mapping files, internal administrative documents, and raw internal archives are excluded.