10 year old home alone.....?

i stayed home for about that long when i was in 5th grade (when i was 10) and since your work is very close he can call you or even go over there if he really has too. i would allow him some more freedom though. i walked over to my friend's house when i was about 7, she lives on another street and i just had to call when i got there. and he should be allowed to play outside without supervision unless there is a pool, or VERY busy road RIGHT next to your house. just review some rules with him like Call me when you get home and Never answer the door when i'm not here, or if the phone rings and they ask for you, instead of having him say that you're gone, just say that you're busy and can't come to the phone now. he should be fine if he thinks he can handle, give him the chance.