http://www.graduateopportunities.com/your-career/undergraduate-programs/
This highlights it well enough
Cadetship = Full time/part time paid work for a company (such as say, EY for a well known one) while completing your degree
Co-op Scholarship = Your course is sponsored by industry leading organizatons and structured specifically with this in mind. You also get given placements at your sponsor corporations (us BITs get 2 6 month placements over a 3 year course) and exposure to an array of other industry related oppurtunities. Your placements are subsadized by a scholarship worth a certain amount
A scholarship is simply getting paid a sum of money for studying at the University