When is a runner out for entering the dugout?

[kylejt]

Here's the deal guys. I'm in charge of about 30 Junior umpires, ages 11 to 17. Most are pretty good, and some have gone to the week long in San Bernadino. But every once and a while I get to unwind some things that they've done, like the last two situations. I'm just looking for some guidance on how to handle them.