1) Definitely not cool 2) Definitely not with it 3) Dweebish or nerdy 4) Geeky 5) Hardly with it 6) Lacking coolness 7) Lacking the cool quotient 8) Like a geekazoid 9) Like mullets 10) Like Urkel, not the Fonz 11) Nerdy 12) Not among the cool 13) Not at all with it 14) Not cool 15) Not cool at all 1) Nedy 
Unhip is slang for unaware, unfashionable.
ill-informed about or unsympathetic to current fads or trends.