WARM-UP: Solve the Case!

Here is a little story where you need to figure out what happened based on the given clues. 

Ms. Grey

Detective Drosin

Detective Drosnin stopped by Ms. Gray's house to inform her that the man who had been stalking her a few years ago had just escaped from prison. She seemed to take the news fairly well, and was very polite, though she didn't invite him in. 


"You know how demented he is, I'm worried that he'll come after you. Who knows what he might try!" Detective Drosnin said. 


 "Oh, I'm sure I have nothing to worry about," she replied. "Would you like me to assign a security detail to you?" he asked. "Oh, no. I'm a teacher for heaven's sake! Having bodyguards following me around would just scare the students at my school." 

Mr. Mustachio
The Creepy Stalker Guy

 "Well, please give me a call or send me an email if you see anything suspicious at all. In fact, send me an email later no matter what, just to let me know that you're alright." "I will definitely do that!" Ms. Gray replied. 


Detective Drosnin got in his car and started back to the station, but after only a few minutes his phone buzzed to inform him that he had an email from Ms. Gray. It read: This morning I tried a fun new seating style for the kids during the morning assembly. I helped arrange them into rows of twenty one. The kids didn't care, but I really loved it. I liked the second column the best. 


 "Why on earth would I care!?" he thought to himself. But then he remembered her passion for codes and realized she may be trying to tell him something. He took a closer look at her email, and couldn't believe what he found! Can you tell what she was trying to say? 


 Would you like a HINT?

Detective Drosnin realized that the message was not only in code, it was also the instructions on how to break the code!