Kyle Simpler, 56, teaches English at Burleson High School in Burleson, Texas. When he walked into his classroom on Thursday, he was greeted by a collective "Happy Birthday!" as students approached him with gifts and cards, wished him a good birthday and began singing to him.

Simpler held back tears when he saw a cake the teenagers had brought for him and as he surveyed the classroom, which the students had decorated with streamers and balloons.

Overwhelmed, Simpler stood back in surprise and thanked his students.