Does my crush like this girl. He is always talking to her and I'm not sure if it's flirting or not. She doesn't like Him though and they have known each other since kindergarten ( we're in 7th grade now)?

This really does sound one sided as he may like her a lot but she has no interest in him whatsoever. Sometimes people just have to learn lifes lessons the hard way like your friend like there is no way on earth for anyone to make another feel the same way about us as we do them.  He wont listen to you here as hes following his heart instead of his gut instincts and the heart does and will lie so let him be and one day he will experience his first major heartbreak