The Maintenance period for ALL patients will last for 24 months. If you have ALL, you will receive vincristine by vein every month. You will take dexamethasone by mouth for 5 days every month. You will take 6-Mercaptopurine by mouth once daily. You will take methotrexate by mouth every week. You will receive intrathecal methotrexate every 3 months for the first 12 months of maintenance. You will have a spinal tap with spinal fluid tests during the intrathecal methotrexate dose.