I have been told don't do cards for kids and I would repeat that to nearly all magicians. The reason is that unless you are experienced with the pace and simplicity of kids then you can loose them very easily and this is unprofesional.
I can also however relate to Michael Kras as I too have done cards for a two year old who loved it.
I don't for one minute think they understood any of it though.
Colour changes like erdenase are good. But if you are in an audience situation I would steer clear of cards for kids under 9. I am not saying you will not get a good reaction from the kids but there may be some kids there who don't understand what went on and just clap because everyone else does. If you are a pro then why loose perhaps 50% of your audience just because YOU want to do cards.
Kids magic works with props that kids handle all the time, like a hat or a box or a bag etc. They never handle cards at very young ages so have no concept of wether a card should be doing what it's doing. There's a magic box in the corner that shows moving pictures, so cards doing strange things well why not?(whats so strange about a card that changes colour) I should be able to get a group of kids under 5 cheering at anything once their wound up enough, do not think this is due to them understanding the miracle you have just acheived. They probebly loved the face you pulled half way through and dont give a second thought to the trick itself.
I am not saying don't do it, just be slow, explain properly and simply.
And be a bit more realistic as to what they are cheering about.
I understand your frustration of people labeling cards as adult only. I once told a kids magician that I did cups and balls for kids, he went through the roof. It's not a kids trick. You cant do that for kids etc.... Well if you say here is a ball and here is a cup, slow it down, and now I am doing this then they all can follow it no problem.
This is the main reason why i will say to guys doing their first kids show to stay away from cards. They will have no idea of the simplicity required and may go into it at adult pace which will cause the problems. They will use adult patter. "take the deck" "here is the pack" etc. Kids should be told "here are some cards, the backs are all red and the fronts have numbers and colours on them"
An ACR with blank cards with their drawing on one of them would be good way of creating this simplicity on a child like level.
I have done a normal deck, kid takes card, writes on it, places it back in the deck, then I spread the deck so all cards are blank except his card. Again very simple as values and suites are avoided. To the kid the numbers and pictures have vanished except HIS magic card.
WARNIG: They will now want to examine the deck (due in the main to marvin magic sets all having dodgy packs) You hand them the cards. They rip them to peices. And as I am a tight git this is another good reason to not do cards for young kids
