how do you stop kids from stealing?

Make him understand continuously by giving moral teaching.If then also he does so then ask some one else to make him understand,because our own kids sometimes think that we are just talking unneceserily and uselessly to them and they don't understand.If some outsider gives the same teaching he would definetly follow and give him examples of other childern,take this in mind not to let him feel down while quoting him others examples.This stealing habit has to be controlled immedeatly to prevent him from doing such activities in the future.Once this habit is rooted permanently, then it would be very difficult to put him back on the correct track.Ask others your near and dear ones for any advices if they have.Mind not to treat him harshly and badly,it may leave even bad impression on his mind.Encourage him for what ever he does some thing nice and good things.Even encouragement on small incidents will inspire him more that way you can win his heart and he might follow your guidence.May God Bless.

Depending on the age of your child I would try to teach the child that stealing is wrong by taking something of their's and hiding that from them and when they ask where is it? then try to explain to them how you feel when you cannot find your items and ask them do they like having their item gone and take it from there.