I know, its so hard these first time experiences for both the child and the parents too! Wait until they go to college!!! but my advice applies to parents with both young and older children. As I tell my parents, the more together and less emotional you are, the better role model you will be for your child. You want him to feel safe and secure and happy with this experience. Please do not let him see you cry. This is going to cause him a lot of anxiety about leaving. If he senses you are sad and unsure about him taking the bus, these insecurities may transfer to him. if the teachers are recommending him to take the bus and get this routine started this way, I would take their advice. Plus he has been on a bus before so that should help a lot. Save the tears for after the bus gets around the corner. You can do it!! keep you chin up!! Maybe send a note with him the first day and ask his teachers for feedback on how he did. This should reassure you about how he did.