Hi Wanda, buying life insurance for your grandchild may be a good idea, but even if you can purchase a policy without the parent's knowledge, doing so sounds an alarm that demands a response. Also, an insurance policy may be but one vehicle to support funding college. There are others you may also want to consider. I see many points to discuss in your question. I recommend you seek an insurance agent in your area- someone you feel comfortable with and is sensitive to your concerns.
I hope my response was helpful and I wish you the best.