Some good thoughts on "sucker tricks" (gotta love that name ......
gee , why do so many people hate magicians ? ) at this link :
Thoughts on doing "Sucker" tricks
For kids these types of effects can be ok if done in the right spirit . They enjoy the "game" where they try to outwit the magician . Even so, I think the sucker trick is best handled if it is done as a magical twist at the end that happens to both the magician and the audience , an unexpected ending that leaves you (the magician ) just as baffled as the kids . It's an attitude thing. As long as it's handled as a magical turn of events , not as a put-down to the audience then I think it's fine.
For adults it's more of an issue. Samuel Patrick Smith (a very successful kids show performer ) mentions the issue of "sucker" tricks in one of his lectures. If I recall correctly, Smith talks about one time he purchased a Die Box , with the classic sucker routine . He tried it out on a friend of his and when he finished it he asked for her reaction. She said : "oh, yeah, everyone just loves
to be made to feel like an idiot " .
Something to think about .