3D drawings of a 16-year-old boy

Are the 3D paintings below very realistic? You will definitely think that this must be the work of some master. No! These works were created by Joo Carvalho, a 16-year-old boy from Brazil. He did not use any high-end painting tools when creating them. Brushes, ballpoint pens, and pencils are just a few commonly used tools. First, use a ballpoint pen to randomly draw wavy lines on A4 white paper as a background image, and then create a 3D painting on it. The final effect is simply unbelievable. Was this really drawn by a 16-year-old boy?

The following pictures were drawn by Joo Carvalho when he was 15 years old.