Childhood tumors, also known as pediatric tumors, are abnormal growths that occur in children. These tumors can be benign (non-cancerous) or malignant (cancerous). Here are some types of childhood tumors:

1. Neuroblastoma: This is a cancerous tumor that usually starts in the adrenal glands, which sit on top of the kidneys. It can also develop along the spine, chest, abdomen, or pelvis.

2. Wilms' Tumor: This is a kidney cancer that primarily affects children. It is also known as nephroblastoma.

3. Retinoblastoma: This is an eye cancer that begins in the retina, the sensitive lining on the inside of the eye.

4. Brain Tumors: There are various types of brain tumors that can occur in children, including Medulloblastomas, Gliomas, and Brain Stem Gliomas.

5. Leukemia: This is a cancer of the body's blood-forming tissues, including the bone marrow and the lymphatic system.

6. Neurofibromatosis: This is a genetic disorder that causes tumors to form on nerve tissue. These tumors can develop anywhere in the nervous system, including the brain, spinal cord, and nerves.

7. Osteosarcoma: This is a type of bone cancer that usually develops in teenagers. It often originates in the long bones of the body such as the arms and legs.

8. Ewing Sarcoma: This is a rare type of cancer that occurs in the bones or the soft tissue around the bones.

9. Rhabdomyosarcoma: This is a cancer that begins in the muscles and can occur anywhere in the body.

It's important to note that while these tumors can be serious, advances in treatment mean that many children with these conditions can be successfully treated.