Yes my daughter is currently a month old, but when she gets a little bigger I'm planning on enrolling her in gymboree classes! They have them in paramus, and you can look them up online on their website!
See if your town has a MOMs club. You can check on Meetup. If they don't, there may be something similar with local moms and kids around the same age as yours. The group in my town has activities every week so I have found out about so much in my area that I wouldn't have known about. I live in Wayne but some things are in the surrounding areas too. We pay $25 per year in dues and it's so worth it!
Re: Bergen county question
this should say Paramus, nj