Do you know what kind of snail my sons are? I think they’re just baby garden snails but I’d rather ask the expert :3
Ooh, man, this one is difficult. Juvenile snails are super hard to tell apart! I can say for sure it's something in Stylommatophora (though that alone isn't saying much, since most terrestrial snails are in that group). It really depends on where you found this little guy, too.
My gut instinct is to point at Bradybaena similaris (Asian Tramp Snail), since the thin stripe running over the shell is highly reminiscent. But it also looks a lot like some European snails, such as Euhadra sp. and Monacha sp. Or, as you suggest, maybe it's a young Cornu or Cepaea.
Anyone else have thoughts? I'm especially curious about the opinions from people who breed snails, since they'd have the most experience with juveniles.