I have just created two families, and I want two of the teens to meet and fall in love.

Using Cheats or The Insiminator, or similar, you can "spawn" another residential sim onto the lot, simply get a sim to great them and they will stick around for awhile, but you can always call them back

I always like to take my sims to community lots- it's a lot of fun to hop them from lot to lot searching for someone to meet. Not so much fun if you don't have the later EPs that allow walk to lot, though.

I tried that once, wanted one of my sims to meet a certain sim and took her all over the neighbourhood hoping she'll meet the other sim on one of the community lots. Didn't happen. But it was kind of fun and I noticed that sims tend to hang out in community places that are close to their homes. You could get them to meet on a community lot easily if one of them works there and you get the other sim to visit the lot.

Get apartment life and move both families into an apartment room next to each other.It's easy to meet teens this way.That's how Morty's son met his girlfriend.I moved them into an apartment and I move the teen girl and her mom into the room next to them.

I use a hack that allows your sims to phone anyone in the neigherbourhood, regardless of whether you've met them or not. That's how I get specific sims to meet if I really really want them to! Here's the link if you're interested:

http://nene.modthesims2.com/download.php?t=72672

Going through the phonebook to find the particular person you want to call can be quite annoying at times, but I got used to it pretty quickly!

I did that with my recent Sims families. I went to the community lots or stalked the sidewalk just in case they happened to walk by. I wouldn't recommended it though, it could take quite awhile unless you're lucky.

You can create a new neighbourhood and move the families to that and then hope that when the teens go to school they meet and become friends and fall that way.

That was what I did with two of my teens...only the on girl ended up attracting three siblings (two boys and a girl).

With apartment life they can knock on their neighbors door.With teens they ask the teen to come out.With adults adults knock on the door and walk in.Apartments also work for children.I tend to make my sims bestfriends as children who I want to marry.Once they become teens they can already try for their first kiss and go steady then marry when they get to be adults.Morty's son thou met his girlfriend as a teen.

Another thing with teens in apartments your teen doesn't always have to knock on the door he may see her in the common area around the pool or hottub.Apartment life makes it easy for sims of any age to meet because they are in rooms next to each other.

Actually, if you use Inge's Teleporter bush, you can summon the sim you want to meet by that.
http://www.simlogical.com/sl/Sims2P...Teleporters.htm

I noticed that too, at least the majorly of them, but you do also get the odd couple that have walked from 2 neighborhoods just to visit a park.
But glad its tuned that way, otherwise some sims will never meet.

And if all else fails, play another sim, and get this sim, to make friends with both of those teens, then arrange a house party, then they will surely meet.

Or if anyone in the household knows anyone in the other household, you could have that person get friendly and use the Invite Household feature and hope the one you want comes along.

If all this still fails, you can always send those 2 teens to University if you got the EP, and move them into the same dorm, then they will surely meet.