How do you find it a participle in a sentence?
Like Bored students, here bored is a past participle that modifies/explicit ==students.
Participle is a verbal and always functions in a sentence like an adjective, just keep in mind.
Gerund is like derived by a verb too adding ing but is always it acts like a noun.
Like--Seeing is believing.
Here seeing ==sub, believing==object. both act like a gerund==nouns.