Look after yourself; if you're sad or worried, talk about it, or do things that help you move it on, don't bury it and become inactive There are many helplines available or your GP can point you to counselling services. Use them.
Helping yourself helps your family, ignoring your own needs won't help them. Even if you haven't lost anyone you may still be feeling tremendously upset. For those who went through the earthquakes, you may have been triggered by many parts of this event - the emergency response, helicopters, cones, flowers, sounds, powerlessness etc etc. Don't ignore these feelings, they are perfectly valid reminders of the danger you have been in. Use the help services that are being offered.
Help children grieve by allowing their emotions and not shutting them down. Find ways for them to express themselves - children do this through play, drawing, acting things out - don't be surprised or angry if they play with imaginary guns or emergency vehicles, it's part of working through it.
Make life predictable. Talk about routines, changes to routines, bus/car routes that may have changed with road closures, anything that is different. Keep doing the things you do as much as you can.
Decide what your 'line' is and repeat it often, so that it becomes a habit in their heads - e.g. "This is not what happens in NZ, it is an unusual situation, the trust you have in the world has not changed."
Take care to look after, reassure and comfort, but also allow them to be competent and confident again - don't squash their efforts to be back in their lives and don't allow them to avoid too long - ease them back into it.
Warn them about the increased police presence, that there may be guns, and there may be helicopters (especially as the sound of the helicopter may be distressing), and that these people are ensuring our safety, showing the world that we are well protected.
The MOE is having teams on the ground in Christchurch and at many schools - there will be resources and people available. Use them and encourage your kids to.
Give love, give hugs (if wanted), think about how your little ones like to receive love and do that. Do it for yourself too.