On the surface, the lowbrow humor and plot seems aimed at children. However, the central premise of selling your soul to Satan introduces themes far more complex than most kids would grasp. And while there are lessons on honesty and doing the right thing, as well as a subplot involving a father learning to trust his child when faced with the incomprehensible, these things might resonate more with adults.
The humor, while aiming for lightheartedness, often comes across as juvenile, which grated on me. The moral lessons appear too nuanced or misplaced for kids to grasp. So I'm not sure if this is really a family movie or just one that has something for everyone in the family.
Kids can just endure the boring efforts at moral quandary while parents have to suffer through jokes that haven't been funny since they were in elementary school.
That said, the performances are great. Jack Black just steals every scene he's in. The subplot involving the parents, particularly the father's arc, is great. But the narrative as a whole, fails to dig deep enough into its more complex elements, like a child's struggles with dyslexia and the implications of accidentally summoning Satan.
The ending, for me, falls flat and feels contrived. It's as if the writers needed to wrap things up. The protagonist doesn't resolving anything so ending feeling unearned.
As a movie to play in the background, feel free to the queue this up, but don't feel you have to sit and watch it. You can get all the jokes and plot points while still cooking a holiday dinner for twelve.