Here is a great exercise to reinforce CONCATENATE, UPPER, RIGHT, LEFT, LOWER functions. Get your students to create their own password generator based on various factors.
In the image below you can see how the first 5 columns contain various data. Column 1 is the lowercase alphabet, Column 2 contains numbers descending from 26 to 1, Column C is the alphabet descending but in uppercase, Column D is ascending numbers 1 to 26 and Column E are special characters (Shift key 1 to 0).
We then have a first name and last name in Columns F and G. In Column H is where the magic happens!