"Yes, my children go to school."
Translation:Да, мои дети ходят в школу.
Shouldnt we have used идите instead of ходят. As the children are going to school they are not walking around the school. As i get it the meaning of ходят is to walk around or to walk in multiple directions.
Shouldnt we have used идите instead of ходят.
Идите is the plural (or formal) imperative of идти. It is not the word you were thinking of - you meant идут.
My children go to school carries a connotation in English that my children attend school. That same connotation exists in the Russian phrase, Мои дети ходят в школу. In such a construct, ходят = go.
My children are going to school carries a connotation in English that my children are actively on their way to school. That same connotation exists in the Russian phrase, Мои дети идут в школу. In such a construct, идут = are going.
Ходить indicates habitual action (like regular attendance as above) or a generic description of walking. Мои дети ходят on its own might simply indicate that my children walk - not crawl.
Please review the declension table here (https://en.openrussian.org/ru/школа) to review школа's cases. You will find it is not genitive.
It is not prepositional because в школе (prepositional) would mean that the children walk inside the school, not that they go to the school.