2004 honda civic cranks slowly in cold weather?

So I'm a 17 year old boy and i have a 2004 Honda civic with 110,000 miles on it and lately its been really cold were I live (about 20 degrees) and the car sits outside. Well when I leave for school in the morning and its that cold, it often takes a few extra seconds to kick over and then when it sits in the parking lot all day at school it does the same. Now I get that cars take longer to start in the cold but I just got this car this past January and it came with a BRAND new battery.

Brand new battery just means new. What quality battery is in it? Quality is given by the Cold Cranking Amps (CCA) rating of the battery-----this will be on the sticker on the battery. A cheap battery will have a CCA of 400-500 and will not provide much starting power in cold weather. A qood quality battery that retains its start power in cold weather will have a CCA rating of 600-700. Check your battery and let us know what the CCA rating is before we offer more advice.

Are you not going very far, with your lights and heated rear window and heated mirrors and music playing? You are likely draining a lot more from the battery than the alternator has a chance to put back in, on what I assume is a short journey.
It wouldn't hurt to just start and run the car for 15 mins with NO current-draining circuits running. It should be easier to start for the journey home. You can also maybe wrap the battery with a heat-reflective and insulating jacket, for the very cold Winter months.