1979-1987 "The Kids Of Degrassi Street"
This logo was used for the original show which was only 26 episodes long, which ended in 1986.
1987-1989 "Degrassi Junior High"
This logo was used for the 3 seasons of Degrassi Junior High, followed by Degrassi High.
1989-1991 "Degrassi High"
They used this logo for 2 seasons of Degrassi High, which ended in 1991. After Degrassi High there wasn't any Degrassi until 10 years later when Degrassi: The Next Generation came to TV. Despite the TV movie "School's Out" that was released in 1992.
1992
This was the movie that was released a little after the finale of Degrassi High...next was the premier of Degrassi: The Next Generation that premiered in 2001.
2001-2010
This was the logo for the first 9 seasons of the show.
2010 -
This is the current logo of the show. After the 10th season premiered they dropped "The Next Generation" tagline, although it's still the same show.