Put out stuff for them to do, like coloring books. Avoid using breakable dishes in the buffet.

Or, don't invite them all. Sorry, I'm biased here.

Oh, it would be such a shame not to invite the kids! Especially if you are a person who wants to include them!

Finger foods would be good. Reasonably plain "I have eaten that before" foods would appeal to children more than fancy stuff with interesting sauce. If you have any food or drink which is particularly hot and spicy or alchoholic, be sure to have that labled.

Children will appreciate Christmas music like you find in the stores these days, the type of stuff we all hum in our heads. Children would be less appreciative of Manheim Steamroller or the entire Handle's Messiah.

If the children are toddler age, mostly you would want a safe place for them. Parents of that age need to really be supervising them, so a special room for the little ones would be where the moms would be as well.

If the children are older than that, a craft table might be nice. Elementary age might like a variety of materials to glue onto a piece of cardboard to make a Chrismas picture. I would put such a table in a corner of the living room. The kids would still be part of the general party. Parents would be able to keep an eye on them. But both parents and children could have their own conversations without bothering the other group. Girls, on average, will continue to enjoy doing craft things at an older age than boys will. However, it seems reasonable that if a child feels too old to do the children's craft, then properly participating in the "adult" part of the open house would be the most logical activity. And be sure to let the kids know that they can do the craft if they WANT to. Many children become shy if they don't know the other people well. These children are likely to want to stick with Mom and Dad, even if it is boring.

It is extra work, but maybe set up a special children's buffet table with the more familiar foods, beverages just for them. Decorate it just a nicely as the "adult" table -- make it seem something special for them rather than a separatist thing. Perhaps a craft area with something that they can make a simple ornament?

I have to admit I don't spend a lot of time around children, so that's all I could come up with.

Personally, I enjoy Christmas type gatherings where children are included as part of the group, rather than segregated. The most recent open house I went to it was just that. Nothing more; nothing less.

If you want to be inclusive, give the children a role, such as "elves" passing out little gifts to guests. They don't have to be in costume, or anything elaborate like that.

Or, have Santa Claus appear. Our friends did this and it was fun for the adults as well, because we were trying to figure out who was behind the beard. :)

With an open house, I realize these ideas may not work exactly, but hopefully they offer an angle. :)

Give them something to do. Most of the problems about kids at parties is that they are bored out of their minds. I like the idea of setting aside an area with a table they can sit on the floor around, with games and toys they can keep occupied with, as well as their own little buffet area with child-appropriate foods.

If at all possible and appropriate - even hiring a "babysitter" to supervise and cater to the kids is a good idea.

The children will be happy, the parents will be happy, everyone will be happy!