If children are brought up to sit at the table at home until the meal is finished and not get down and run around in between courses, then it is easier to get them to do the same in a restaurant. Give them things to occupy themselves and allow them to take part in the conversation, but do not allow them to get down.

Three words "Coasters and Pencils" haha

Something that my aunt taught me is to bring a color pad and some crayons with you when you go out. It really helps keep the kids entertained at least for a little while. 

Hi there.  Welcome to Minti.  This is a bit of a hard question as you don't emntion (a) if you are talking about your own kids and (b) how old the kids in question are.

Also different countries and cultures have different expectations of children in social situations.  We lived in Malaysia from when our son was 2-4 and kids rule to a point thre.  As we arrived at restaurants the staff would scooop our blonde haired, blue eyed child up and parade him around like a trophy, take him on kitchen tours, pretty well give him anything they thought he would like.  The culture there puts a lot of emphasis on small children and they are allowed to walk around while they are eating (a maid will usually be in tow, spooning their food in them).  We didn't allow that because we knew eventually he would have to return to his own culture, so he was always made to sit down in a baby chair to eat until he was old enough to sit in a regular chair.

Moving home to Australia when he was 4 was so far removed from that and he was expected to sit down at the table and enjoy himself but not run around or disturb other guests.  Restaurant staff there didn't fuss over him or any other child usually, and he wasn't allowed to wander around playing with children of other diners.  It wasn't too hard for us though, as the whole time we were in Malaysia we did tell him that when he ate in restaurants back home, so even at 4 he had had that programed into him and knew what to expect (to a point).

Personally, I am a big believer in children behaving in restaurants and sometimes I am appalled at what some parents let their kids do to disrupt and annoy other guests who are paying good money to relax and enjoy their meals.

So really, any advice anyone gives you here might be fruitless unless you advise ages of the children and how the local culture and expectations of children works.  Sorry I can't be of more help.