Movement of the human body in the sagittal plane (the plane which slices the body between left and right) can be simulated with a simple model made up of four rods and a sphere. In a situation where the torque about the center of mass is zero (such as diving into water) the angular momentum of the body about the center of mass is conserved. In a situation where the torque about the center of mass is non-zero (such as jumping or swing by one's hands from a bar), the angular momentum of the body about the center of mass has a rate of change equal to the torque. Based on these principles, as the configuration of the model's limbs changes, the orientation of the model changes accordingly. Using this model, a software authoring application called Director (by Adobe) was used to program simulations for Physics Curriculum and Instruction. The simulations demonstrate the three above-mentioned activities: diving, swinging, and jumping. A user of this software can determine how the "athlete" will move his/her joints over a period of time, and the resulting motion of the body is shown.