Roberta, I have the same leaders, velcro-ed to my rollers. I've never taken them off. I just pin the backing to the take up and backing rollers' leaders. I pin right into the canvas. I float the batting and top.
Since you and your mom are just starting out, you will probably be most comfortable following the instructions from the class for the first couple of quilts. Once you gain some experience, I would take a few minutes and look at some of the 'how to load a quilt' videos on you tube and try just pinning. everyone has their favorite technique or tool to do this.