Durga Puja is traditionally performed in Bengal and other parts of Eastern India during Dussehra or VijayaDasami.
She is Mother Goddess, Shakti (or the divine force) and an incarnation of Parvati, Shiva’s wife. She was manifested to kill Mahishasura, a powerful demon who could not be defeated by man or God. Only a woman could kill him. The victory of Durga over Mahishasura (good over evil) is celebrated on VijayaDasami.
Here is a easy Durga slokam to teach our kids:
Sarva-mangala-mangalye Shive Sarvaartha-sadhake
Sharanye Trayambake Gauri Narayani Namostute
Goddess Parvati is the consort of Lord Siva and is worshipped as Sakti. The Puranic literature describes her as having many forms, including Durga, Candi, Kali and Uma.While Siva symbolizes the efficient cause of the creation, Sakti symbolizes the material cause.
The one who is the auspiciousness of all that is auspicious (sarvamangalamangalye), the consort of Siva (Sive), who is the means of accomplishing all desires sarvarthasadhake), who is the refuge of all (saranye), the three eyed one(tryambake),the fair complexioned one(Gouri), Salutations to you, Narayani(narayani namostute). Salutations to the consort of Sri Narayana (Sri Lakshmi Devi), who is all auspicisous, who is the Mastress of all, who blesses devotees succeed in their efforts and who is the refuge of all.