Some activities for younger children while mom or dad is serving at a UT post...
The Counting Chain
Unlike most chains this one actually counts how many days daddy/mommy has been away, the perfect thing about this is it can be used as decoration. This is the same type of chain that a child would make in school to count down until Christmas. As every day passes, write something you did that day or remember. It' a great way to remember everything they want to tell the loved one that isn't there. Once daddy/mommy is due home, use the counting chain as a welcome home gift...it'll definitely be long enough to decorate the living room.
The Keepsake Box
Get a shoebox and have your child decorate it. Inside the box they get to add something every day or week (depending on what you want to try) and once daddy/mommy comes back they can tell them all about the items.
These ideas are courtesy of this website.
Also, remember to stick to routines. Routines will help your child feel secure. As time goes on and she/he feels more comfortable, ask your child to help you create new family routines, such as Backward Day (try eggs for lunch, sandwiches for breakfast). Take care of yourself by including physical activity in your routines: a family walk, a game of tag, or dancing to favorite tunes. Also, eat (and serve) good foods to feel your best and get plenty of sleep. By keeping yourself physically healthy, you’ll keep yourself emotionally healthy, too.
More resources can be found at this website.