You can send your child on the bus, train, or walking if you don't drop him/her off at school.  Riding bikes are fun, although it depends on the ages.  Too young kids maybe a risk on the road alone.  And helmets are always a must if you choose this option.
The following articles are about bike safety.
http://www.education.com/topic/child-bike-safety/
http://www.education.com/gift-guide/item/Prod_preschool_skuut/
Thanks,
Rachna

For kindergarten and first grade, we walked our daughter to school every day. We lived only a few blocks from the school.

Next year, for second grade, we are considering bus or carpool, because we've relocated. Her new school is atop a steep hill and a bit too far and strenuous to walk or bike from our house.

For parents of children who will get to school via bike, below is a link to the Parent's Guide to Youth Cycling.

Thanks for asking!

I wish we could ride to school.
My sons elementary school is 2 miles from our house and crossing few major roads. We'll be taking him to school by car.

I'll reconsider riding to school this in few year, after I'm sure he can cross roads safely by himself.

yes

Cool. I think biking is a good option, since we live close enough to the school, and only minor residential roads need to be crossed.