A malignant tumor of childhood, that metastasizes to bones most often, is:

Neuroblastoma is the most common solid neoplasm outside the CNS. It arises from neural crest tissue of the sympathetic ganglia or adrenal medulla. It most commonly metastasize to bone, bone marrow, lymph nodes, liver and subcutaneous tissue. It has a predilection for metastasis to the skull, paicularly the sphenoid bone and retrobulbar tissue. Ref: Essential Pediatrics By O P Ghai, 6th Edition, Page 573; CURRENT Diagnosis and Treatment: Pediatrics, 20th Edition, Chapter 29.