Can we do Odos 2 or a later set in the series with a group if they haven't done Odos 1? 

 

It is not a requirement.

 

Each set in the Odos series can be done without doing a previous set. 

 

Ideally the series should be followed from Odos 1 to Odos 5, because the level of the sets corresponds with the developmental level of the child. 

 

A child who has not done Odos 1 and 2 for example can begin with Odos 3 and will in no way be "behind" the other children. It will still add tremendous value to the child.