Kat first apologizes to Patrick about the whole looking-through-the-bag-thing and the foot (she stabbed a nail into it) in this episode. A cheerleader has pulled a tendon and Bianca may get to cheer. The two girls head home for the day, Kat realizes that her car isn't so good for the environment, even though she's a radical supporter of saving the environment.
Mandella suggest converting the car to biodiesel. Kat plans to do it herself. Cameron explains to Bianca that he's NOT gay. Chastity will allow Bianca to cheer at the next meet if she can help Joey do well on his chemistry lab. Walter hears Kat's plan for the car and is concerned that Kat can't do it. Michael says that Cameron should do something out of a movie to catch Bianca's attention. He's going to show up at her house, shirtless and wet and just lay a kiss right on Bianca. Bianca tries to get Joey engaged in the assignment, but it's clear that Joey is very easily distracted.
Kat heads to the school garage where the teacher and students (all male) tease Kat. Kat's initial progress is very bleak. Two kids named Brad and Ray really lay into Kat, even start a bet that she won't be able to finish the job. Patrick is also in the class. Bianca is trying to get Joey a good grade. Joey says he's not interested in football, but modeling. No one gets it, he says. Kat continues working in the garage. She messes up Patrick's shirt with oil, causing him to remove it. Kat does stare for a minute, but quickly defends that she can successfully complete the conversion to her car.
Chastity calls to make sure Bianca and Joey are focused. She spills cola on Joey's shirt so he takes it off and Bianca heads off to wash it. Meanwhile, Cameron shows up – shirt-off, wet, ready for the kiss – but Joey answers the door! Cameron leaves and Joey sprays water on himself to get rid of the stickyness of the cola. Walter comes home and sees all of this, which causes Walter to kick Joey out. Joey suggests Bianca become a model too, but she dismisses this.
Kat is frustrated with the car and she ends up staying late. Walter comes by with dinner. Kat is hard on herself, but Walter says she is also stubborn and says to try it again in the morning. Walter stays to help Kat out to prove to the shop boys that she can do this. Michael comes up with another solution for Cameron – aversion therapy to get his mind off Bianca. Chastity confronts Bianca – apparently Joey is now quitting football because Bianca suggested that he might get injured while playing. Now Bianca has to get Joey to get back on the football team again. Bianca tries to convince him to go back to football, which he eventually agrees to. The shop class comes back the next day to find the car completely converted. Kat's even filling up the gas tank with some of the caféteria's cooking oil. She turns the car on and it successfully starts. Patrick says he's impressed. She drives off out of the school's auto shop with money from winning the bet. Meanwhile, Cameron is not ready to give up on Bianca.