Interested and interesting etc
…ed – Interested, bored, excited, amazed etc say how people feel, so it is connected to people.
…ing – Interesting, boring, exciting, amazing etc describe the people or things that cause the feelings.
The party was surprising.
I was surprised by the party.
The book is interesting.
I’m interested in the book.
The movie Avatar is amazing.
Angelina Jolie is an amazing actress.
Source: Practical English Usage – Michael Swan