As my dad used to say...
Never co-sign for anything you aren't prepared to pay for yourself.
Not saying your child would not pay his loans, but things happen in life.
If you think it's a good deal for him to take out these loans for his education, and are prepared if you must pay, it's worth it. Like some one suggested, a life insurance policy for the amount wouldn't be a bad idea, but most co-signers that end up paying for others loans aren't because of a death, so just be prepared.