Girls and children of poorer families might be named at the same rite. References to further reading would be helpful. The Isthmian Games were held biennially in even-numbered years before Christ and in odd years after. For festivals read above. For temples see pages on architecture and religion by clicking on the Menu Directory below.
Myths are the stories the Greeks told about their past.
See a specific mythological figure in the Menu Directory. Demeter might be a good choice. Most of their festivals were religious. These involved parades, sacrifices, banquets, music, and dancing. Some also involved atheletic contests.