Ahh, welcome to the world of shin-splints! Yes, writing the alphabet is a great excercise that you can do to strengthen your lower legs and increase ankle flexibility as well.
Another exercise I used to do is heel lifts on a curb or stair before you go for a run. Walk for 5 minutes, do 3 sets of 10 reps of heel lifts, then start jogging. Each week ad 2 reps.
And there is running backwards, or walking on your heels, or toe tapping.
You can switch between these for variety. I have done them all and they work very well.
My soccer coach alternated between running backwards, walking on heels and toe tapping.
The key with the toe tapping is to do it as hard and fast as you can. Start with 3 sets of 10 and work your way up to timed sets
(like 30 seconds
). You can do this at work under your desk!
Since you run intermittently, start doing two of these excercises each week, and hopefully the next time you run, you will see the investment pay off!
Remember, since your shins already are sore, take it easy with these excercises. Take some mild anti-inflamatories and ice your shins after a run. Aslo run on softer surfaces as you start out, that will help a lot! Also if you are very new to running, you should do a run/walk combination, run 5 minutes, walk 1 minute...run 6 minutes, etc...
here are some articles i googled for you; I typed in "shin splints exercises"
http://www.pponline.co.uk/encyc/0161.htm
http://sportsmedicine.about.com/cs/leg_injuries/a/aa010201a.htm
Good Luck! and keep running!