Mommy's not gonna come back and get me!!

I think you should tell him that he is to go with NOONE but you and that you will be back as soon as you finish work. Once he makes some friends and becomes familiar with the schedule of the classroom he is in, I don't think it will be a problem anymore.

I think that at some point all kids go through separation anxiety.  It'll pass.  Just reassure him that you'll be there to pick him up at the end of his day and that you love him very much.

Awww.

Well, give him a time frame for when you want to pick him up.  Ask his teacher what they do at the end of the day and say "I am picking you up right after you play outside this afternoon".  That way he can look forward to that event :).

Good luck :) :)

I think a good coping method would be to give him something of yours, maybe your watch and set an alarm for it and say when the alarm goes off I will already be here. He may take some comfort in that. 

Try making a photo book together of you, him, and your family to give him a familial sense of reassurance. You can make this easily on websites like snapfish or even walmart and you can make them in a variety of sizes so that it fits in his little hands.

Include on the pages pictures of each of your family members he's familiar with as well as photo's of all of you together. Make this book WITH him on the computer.

Then let him take the book with him to pre-school. Explain to him that whenever he is feeling sad he can take the book out and look at it and that will make him feel better and he can show the book to his friends and teacher and explain who all the members of his family are. This will reassure him that you are still there in his life (even after you've left the building and gone to work) and that you will return. 

I suggest putting a picture in the beginning of the book of you walking him into class and a picture at the end of the book of you picking him up and the family pictures in between those. 

Sometimes kids just need a security attatchment, something familiar and home like, to reassure them that they ARE in fact going home at the end of the day everyday. Kids and toddlers have irrational fears just like adults do.

Awww, I bought my ds a little cars watch at kohls. I said look at your watch and I will be here at ONE, TWO, THREE, ZERO! (12:30) he was comfortable from that on because he had some idea our control of knowing when I would be back and then he figured out the routine and knew I would come right after lunch!

I know how you feel, I hope this works!

My son did the same and after a routine of you being there on time to get him, he'll realize everything is ok. My son this year is like, peace out mom, and no worries;)

awe. i like the watch idea.

I would ask him why he thinks you won't come back and then continue to reassure him.  Maybe tell him what you guys are going to be doing after you pick him up so he has some visuals in his head.

I think all of the ideas everyone has shared are really good. Just keep reassuring him and try to not be late so he's not waiting for you after all the other kids are gone.