First of all, there's something off about the quote. It feels wrong, in grammar or structure or something like that. I'm not sure how to deal with that, and how you deal with that could affect the understanding of the text.
1) To give refers to giving that you wish the child to do, probably as a result of the emotions conjured by the parts of the paragraph immediately before the quote.
2) Yes; Teachers and parents praise children to condone their actions or bring out a point, but sometimes they do so in a tone that sounds fake (the parent/teacher is clearly not as excited as he sounds) to onlookers and even the children themselves. The children don't really gain from such praise or methodology, and perhaps throwing such praise at the teacher/parent could show them that what they're doing is clearly ridiculous, as if you'd do it to them (shouting "Nice praising!!!") they'd realize you're being silly, and they'd listen to their own such sayings.
Nowadays, I hear a taste of their own medicine rather than treacle. Apparently treacle used to be used that way, see Wikipedia.