Put A Frog Named Sam in the CD player and the title track will instantly remind you of the Grateful Dead. The psychedelic, swirling guitars might not immediately sound like something a toddler would like, but the rhythmic croaking of Sam (a frog who doesn’t like water and is heading for the big city) is genuinely lovable. And that’s how Ben Rudnick, an award winning, New England-based musician, has always made children’s records. Rudnick melds highly skilled musicianship with fun spins on kids’ interests like milk shakes and race cars, and adds a youthful slant to traditional songs.