Review the sentence:
Poking his head through the unzipped top, Jodi’s book bag was Freddy
the Chihuahua’s taxi.
Poking his head through the unzipped top, a participle phrase, comes right before book bag, an illogical target. The dog, not the book bag, has a head! (Jodi's, a possessive noun, functions as an adjective describing book bag.)
Before you continue, review the rules for misplaced and dangling modifiers.