Hi @Christine_Bolton 
Not sure if I get your problem right, but maybe you can use custom fields or tags to flag them.
If you´re premium you could use rules to automatically drag the tasks between sections.
So, therefore I would not recommend to do this with subtasks.
Check out also @Bastien_Siebman ´s post 🏆 The Asana coolest projects Award - #18 by AnneNynke for some inspiration 
All the best and greetings from Munich