The aim of this study is to evaluate the effect of using a selected dual-task- training program to improve postural stability in children with ataxia after medulloblastoma resection. Thirty patients will participate in this study. Patients will be classified randomly into two equal groups: study and control groups -Both groups will receive conventional physical therapy treatment including mobility exercises, balance exercises, gait training exercises, and exercises to improve physical conditioning. In addition, the study group will receive a selected dual-task training program including balance and cognitive activities. The treatment program will be conducted three days per week for eight successive weeks. The patients will be assessed with the Scale of Assessment and Rating of Ataxia, Humac Balance System, the Pediatric Balance Scale and Functional Independent Measurement. The measures will be recorded two times: before the application of the treatment program (pre) and after the end of the treatment program (post).

Inclusion Criteria:

All children with the following criteria will be in rolled in the study

1. Age range from (5-10 years).
2. Severity of ataxia will be from 15-30 by SARA scale.
3. Children after 2 months of medulloblastoma resection.
4. They can stand and walk with minimal support.
5. They have good cognition, compliance, and ability to understand and instructions.
6. Children receiving radiotherapy and chemotherapy sessions
7. They are medically stable

Exclusion Criteria:

Children will be excluded from the study if they have

1. Any neuromuscular disorder.
2. Visual impairment.
3. Cognitive problem
4. Convulsion.
5. Peripheral neuropathy due to chemotherapy.