32834217_as___Arts___Sciences_Computing__What_you_need_to_know
[Why it matters] When you request your Canvas site you will be given the option of downloading an export of materials from your previous Blackboard site. You'll be able to import this material into Canvas. Support staff are available to help you materials from Blackboard to Canvas. Some instructors find that it's easier to start from scratch and manually build up materials in Canvas. Others may find it easier to do the bulk import. Need help moving materials from Blackboard? Send mail to canvas@pobox.upenn.edu [What you need to know] 
You can move content from a Blackboard site into Canvas
Things You Really Need to Know about Canvas | Arts & Sciences Computing
What you need to know