Each example from Sections 2, 4, and 7 run contrary to the content presented in Section 1 because they allow any user to execute the script. (I realize that the scripts are limited to which users can execute them because of the directory they're in.)
The content says, "Grant execute permission only for the intended users of the script." This makes sense from a security standpoint.
All three lab examples indiscriminately grant execute permissions to everyone (world-executable). IMHO, this is a bad habit to teach student.
As a result, I'd suggest that each of the three lab examples be changed to, to keep in alignment with the content:
chmod u+x <script_name>
Section 5 has this:
The second sentence is technically true, but only because the regular expression is malformed. The $ doesn't go before the search string, it goes after: cat$
Here's the proof:
There are plenty of lines the end with in, but using a regex of $in won't find them..
using the proper regex, in$, does:
Program Lead at Arizona's first Red Hat Academy, est. 2005 Estrella Mountain Community College