How to make certain parts of a RISE program restricted

Thank you Hazel.

I already knew that and have incorporated it into certain blocks.

I guess I'll have to request the user go through the lessons sequentially. That way they'll have the ability to accessing the glossary and reference sections throughout. 

I wish there were a way to restrict certain numbers of the lessons.  For example, if on the contents page, I could have a heading called glossary and references, then under that heading, have the glossary and reference "lessons" (they're not actually lessons.)  set as FREE. then under a different heading, call it, "Lessons" then under that header make the lessons "restricted" forcing students to finish lesson one before lesson two,, etc.