For many schools counting from 1-10 is a basic requirement to test for your first belt. Even though we count in Korean during warmups and throughout the class, many parents want to see and hear the words for themselves so they can help their child study.
There are several Youtube videos on this subject; however, none of those specifically cover counting in a Taekwondo setting.
Feel free to share this with your students as a training aid for your curriculum.
https://www.youtube.com/watch?v=uygTYqTgMTg