Students of the school lined up the road leading to the school to welcome her when she presented her award to the school.
The 41-year old Primary One teacher beat two others to win the coveted national prize and received a 3-bedroom house, GH₵50,000 cedis, life insurance cover from SIC and a scholarship to study abroad.
Speaking at a surprise durbar organised by the management of the school in her honour, Ms Cobson said the selection process was transparent.
She added that given the calibre of people involved in the selection process, made up of veteran educationists, there was no room for bribery.
Ms Cobson explained to the gathering that she first won the district best teacher and later the regional best teacher after organisers of the award scrutinised her works before being adjudged the overall National Best Teacher.
Ms Cobson expressed her gratitude to the headmistress of the school, Madam Emelia Larbie for her support during the process.
She said she owed her success to the headmistress who had been the source of her encouragement.
She also dedicated the award to her colleague teachers and the students of the school.
She further encouraged parents to invest in the education of their children since they were the future leaders.
Madam Larbie congratulated Ms Cobson for bringing honour to the school.
Ms Cobson was accompanied by the National Best Teacher 2nd Runner Up, Mr Joseph Abusah, National Best KG Teacher 2017, Ms Regina Aboagyewa and the 2009 Overall National Best Teacher Ms Irene Essel.