How Does a Paper Airplane Surfer's Wing Washout Angle Affect it's Ability to Turn?

This project requires students be able to fly the paper airplane surfer and successfully maneuver the plane through a turn by controllable slope soaring. (see video below).

Make two paper airplane surfers, one according to the directions, the other without wing washout angle (see photos below). A wing washout of zero degrees means that the wing tip surface is parallel to the main body surface. Trim the planes to fly slowly. How does the paper airplane surfer with no wing washout angle perform in turns? Stability about which axis is crucial to turning an aircraft?

The red paper airplane surfer has no washout angle, the green has washout angle.