Anyone come across great Italian gifts for teens?

Elvis Lives in Trastevere has T-shirts, hats, tote bags, etc. all Rome related.

https://shop.elvislives.it/shop/category/34437677/shopper-e-tote-bag/

If they are soccer fans, the AS Rome team shop will have something, though the soccer shirts are probably going to be closer to EUR100.

If they keep journals, maybe a leather bound one?

https://www.manufactus.it/categoria-prodotto/journals/

Sports related clothing is big there as well as here, although pricey. And there are men's and women's teams to choose from.

If one of them is a racing fan, a cap, T-shirt, hoodie, keychain, etc., could be a good option.

FYI:
Bologna = Ducati
Sant'Agata Bolognese = Lamborghini
Maranello = Ferrari

You'll find souvenirs from each of these brands in Bologna.

Mary, Elvislives sounds perfect. I will definitely check it out. My nephew is very active with soccer. I will also check out sports jerseys.

There is a Bologna FC Store on Via d’Azeglio right off of Piazza Maggiore. I bought my nephew a soccer jersey there. Unfortunately the football jerseys are closer to 100 EUR but there are other items.
https://www.bolognafcstore.com/us/bologna-fc-store

For your girl: costume jewelry such as Murano glass earrings.
Perhaps lovely Italian soaps and toiletries in beautiful packaging.
Leather: bag, wallet, etc.

AS Roma sells cotton t-shirts for EUR 45 and a long-sleeve shirt for EUR 65. Baseball caps are EUR 26-plus. They also sell ceramic mugs and insulated mug at reasonable prices. You should be able to find within your budget.

https://store.asroma.com/en/

As an aside, my 14 yo niece and her younger brother asked for food souvenirs, especially Nutella-related. I got them Perugia chocolate in different flavors and any kind of Nutella cookies I could find from the supermarket. At the airport, I found a package of miniature Nutella jars, which was a big hit with them.

Thank you all for the great ideas!