Warm up and Cool down exercises - help!

I haven't coached for about 6 years and am getting back into it now, but I need help coming up with warm up and cool down exercises for kids around 6-13 years old... any suggestiongs?

Start Running, High-Skip Knees up, In line 10 Tuck Jumps 10 straight Jumps, 10 Straight Jumps to squat. Then stretching to splits (depending on age/ability) V-Sit ups, ankle Rolls, Bridge Up then Roll or Tables for boys and little ones. Arms Out roll neck from side to side up and down. Total Wram Up should be at least 10-15 Minutes with Cool Down at end of class which usually consists of some sit ups, Push Ups or some easy Handstands up on wall mat.

Good Luck!