The children enter 4th grade and decide to immediately take a stand against their new teacher. Their new teacher is named Ms. Choksondik. She is a woman with large breasts and who doesn't wear a bra. Remembering fondly their 3rd grade year, the children seek a way to travel back in time. Two college students that live next door to Kyle offer them a solution using Timmy's wheelchair as the inertia device. The device doesn't appear to work but Timmy can't stop or get out of his wheelchair because of the risk of an explosion. However, when the device's timer runs out, Timmy disappears in time. The children are convinced Timmy is reliving the 3rd grade (in reality he is doing some serious time traveling). They want the college kids to build them another time machine so they can join him, only the college kids are arguing about the number of original "Star Trek" episodes there were. The children work on patching up that relationship. Meanwhile, in an attempt to reach out to her students, Ms. Choksondik demands to see the children's former 3rd grade teacher, Mr. Garrison. No one knows where he is (because they haven't gone to look), they speculate somewhere in the mountains. She finds him living in the mountains like a hermit and seeks his enlightenment, which she does. In addition Mr. Garrison finds his own enlightenment and finally comes to grip with his gayness. He is ready to become a teacher again; only South Park Elementary doesn't hire gay teachers. When Ms. Choksondik begins treating the children the way Mr. Garrison did, the children begin to respect her and are ready to learn.
Kenny dies when the SWAT team uses him in an attempt to deactivate the explosives on Timmy's wheelchair.