The guys are in the driveway, getting ready to tow Kelso and the canoe with the car. Between each shot, Kelso's scarf changes position.
When Eric is in Donna's bedroom apologizing for ruining the dress, she sits down on the bed to listen to him talk about "voodoo nonsense" with her arms crossed. In the next shot, they are uncrossed.
"Low Rider" was not the song Eric an Donna were listening to at the end of their first date. It was a Todd Rundgren song.