This purpose of this study it to characterize the walking patterns of children diagnosed with Acute Lymphoblastic Leukemia (ALL)and Lymphoblastic Lymphoma (LL) at different times in the treatment protocol and after completion of treatment. Their walking patterns will be compared to children without ALL or LL to see if their walking patterns are different at specific times in their treatment program or up to 10 years after completion of their treatment. The investigators will gather data by observing how the child walks, runs, hops on one foot and climbs stairs and by recording walking patterns on a pressure sensitive mat. The investigators will compare this data to children without ALL and LL.