Do you have any advice or can you recommend any resource that addresses
daily exercise drills for kids to improve their fitness and soccer skills?
Of particular interest are drills that can be performed indoors in a
Liz if you are working with children then you should eliminate the word 'drill' and replace it with the word game or activity. Since I do not know what kind of space you have available in which to practice soccer skills and get physically fit. I will assume you are talking about an ordinary home with furniture, lamps, etc.
Having your child move some of the objects away from harms way will be the beginning of physical fitness. Then adding the ball to their movement around the area will accomplish your goals. If it is possible to juggle the ball (without destroying stuff) then it would be wise to begin with that technique. If it is not possible to juggle without damaging stuff then a 'Juggle to Hand sequence would be appropriate. That is, starting with the ball in ones hands -drop it to either instep or thigh and catch the return ball. This can also be accomplished while sitting and watching TV.
You may want to set up an indoor slalom using the furniture in the room as obstacles. Have the child time themselves on successive days in an attempt to beat the old record. I would suppose that going up and down the stair's would become challenging and very demanding physically.
Doing stretching and other exercises while using the ball can be helpful also. You can find a series of these activities in my 'FUNdamental Soccer -Practice of Champions' book.
The bottom line...Use your imagination or allow your child to be creative in being active (using the ball) in a confined area without destroying any property.
Hope this gives you some ideas on helping your child stay active during the winter months.