Is there a love spell for teens in any of the packs?

I don't know about a love potion, but I've found Social Bunny super helpful in shifting the affections of a fellow teen. My teenager kept spamming her crush with flirty messages and finally the pink bar went up and then he was more receptive to her romantic overtures and now they are romantic partners.

But just trying to talk to him in person, he kept disliking her attempts to turn their friendship romantic. I think one of his romantic turn offs might be the flirting category, which makes it hard to build the romance up from nothing, but Social Bunny did it for her instead. 

There's a potion you can brew in realm of magic that helps your sim succeed in romantic actions.  Potion of Alluring Aura, makes sims around the drinker more receptive to Romantic actions.  I think it's level 2 (neophite) to learn it, though.  (Though I'm sure there's a potion shop somewhere on the gallery you can download and have your teen buy it from)

I want to think there's something similar in the various concoctions from the Herbalisim skill, but I'm drawing a blank on that.

With crystal creations, there is a charged crystal that makes your romantic interactions more successful.  If I was in game now, I would check, but I think it is fire opal.  I think.  

Since you have all the packs, you can set the NAP for Free Love For All (I think what it's called). That builds the pink bar for like no reason at all. 

Also, the love festival can help if you both drink sakura tea together and then do all the love festival interactions, like throw petals, mention flirty vibe, joke about getting together, etc. 

But I think the most successful option is the potion of alluring aura from Realm of Magic. 

In the base game there is a rose, and a bucket of champagne that helps romantic actions succeed..  in dine out I believe there is a drink that helps them succeed too. You can make flirty cookies if you are flirty and you might be able to create flirty or romantic paintings ( not sure about that one ).  I do know you can make flirty sculptures from the woodworking table.  I’m not sure if all those things work on teens though.  If you have jungle adventure you might check and see if any relics can help. And I’m not sure if the emotion tree has a berry that can help with it.

I saw the girl getting all hearts and roses with another kid at school and they are both rich 1% ers.  I think I will try the Social Bunny route first because I know she won't come over.  I have asked befoe and she'd rather wash her llama or something like that although she is a good friend with my sim.  And teaching him the magic path could take a while.  Maybe he could also look for another girl.  I noticed there was only ONE girl in the high school when I started so I used the testingcheats mod and changed a number of guys into girls.  Surprisingly they came out looking pretty hot if I can say that about sims.  Maybe I play this game too much.

Spellcastes can use

• infatuate spell: Convince two Sims to get romantic with each other: The two Sims will bet a +10 flirty mood, and will automatically make out. The buff is called, "Cupid's Touch" and lasts 30 mins. Interestingly, casting this on Sims while charged will give the two lovebirds a larger ++ LTR_Romance gain.
• Potion of Alluring Aura: A potion that makes those around the drinker more receptive to romantic conversation

Fairies can use

• Influence Another's Relationship: rank 4 emotion power. You can boost the relationship of two sims of your choice. These can be two adults or two teens. I don't believe teen/adult is possible.

In my experience the fairy spell is the most effective of these options because it directly changes the relation ship bar, not just the flirty emotion. Casting this power twice got the pink bar over half full.

Forget the spells, just allow him to have some romantic interactions with her. Small, at first. He could compliment her outfit, that sort of thing. Just let him be his charming self. Or if you're controlling her, you can let her make the first move.