On 14th October 2018, Brainobrain won the Guinness World Record for the Largest Mental Arithmetic Lesson in the world where around 3189 students were trained together. Children between 4 to 14 years from Brainobrain centres across India underwent a 40-minutes largest-ever session that exposed them to swift computing abilities in Addition, Subtraction and Multiplication. Starting from Single digits to triple digit numbers ranging from 5 rows to 20 rows of addition and subtraction along with multiplication were performed by children with great speed and accuracy. The session conducted by Arul Subramaniam, Director, Brainobrain Kids Academy, ended with a five minutes test that proved the students super fast computing abilities outdoing the calculators. The mega event took place at Chennai and it broke the previous world record of 1073 participants, set by China.