My concept of a "game mechanic" for the Tom Sawyer Scene is too complicating.
I tried to imagine a new sort of interaction as a combination of a weapon system and a dialog system.

Let's try the opposite, a simple dialog system:

Aunt Polly:
- Paint the fence! You have to finish your work until lunch!
Tom starts to paint the fence.

First kid comes, saying:
- That's funny, you are working!

The player gets answers of Tom to choose from:
1. Let me alone!
2. Wanna try it yourself?
3. Don't disturb me, I have to concentrate!

Reaction of the #1 kid:
to 1. He laughs loud, and shouts: Hey, kids come along, Aunt Polly presents a show: Tom at work!
to 2. Eh, you don't ask me seriously, do you? (and walks away.)
to 3. What's so important of your doing?

etc.

This is the easy approach. After this character comes another with different reactions and so on.

But the depth of gameplay is quite small, while you have to read quite much.

Maybe, one can take this dialog and its decisions/options to build a more and more complex gameplay while keeping an ease of use!

The depth of feelings is small, as well.

Though for children it might be good. Children are faster involved because of their lack of experiences and their stronger imagination.

But, for adults the depths have to bigger:

- the depth of gameplay,
- the depth of feelings,
- the depth of experiences!

I wonder how these are relating to each other. At least, I add them to my checklist of game properties which have to recognized while developing a game.