What's the difference between "so am I " and "so do I "?"so do they" and "so are they"
If the first part of your sentence has the verb "to be" then it will be "so am I, so are they."
Peter is very enthusiastic about this event, so am I/so is Mary/so are they etc.
but if you have the other verb in present simple tense it will be do or does
in your sentence it is
I feel that it is weird that Tim becomes so crazy about the stars and so does Mary and a lot of other students.