Simon Van Gelder
| Gender | Male |
| Age | 8 or 9 |
| Hair Color | Dark brown |
| Occupation | Student |
| Grade | 4th Grade |
| Voiced by | Trey Parker[ |
| First Appearance | Roger Ebert Should Lay Off the Fatty Foods |
About
Van Gelder is a volunteer worker for the Tantalus V. Observatory who appeared in the Season Two episode, "Roger Ebert Should Lay Off the Fatty Foods".
He wears the standard Tantalus V. Observatory uniform; a black shirt, with a light blue v-neck shirt and a picture of a dark cloud and sun.