No, you cannot use a Chromebook, or any other Chrome OS device, to access Blackboard Collaborate Classic.
Currently, CDLI is using Blackboard Collaborate Classic for on-line classes and tutoring sessions. Chromebooks and the Chrome OS are not supported for use with Blackboard Collaborate Classic.
https://blackboard.secure.force.com/apex/publickbarticleview?id=kAB700000008P8m