I googled it and here is one...
http://www.habermanfabrics.com/scart/Special_Use___Other.htm
If you hae a few minutes, google, "chalkboard fabric"

I bought some at our Hancock Fabric Store.

Sometimes a dimestore(are there any left?) or hardware store has it. I never heard of chalkboard cloth- we use paint for chalkboard. So this is oilcloth. I've even seen it at a nursery where you buy plants, probably for picnic tables. It comes on rolls like the 6 ft indoor-outdoor carpet. Maybe your fabric store, I remember relatives had oilcloth on kitchen table yrs ago. Hope you find some.Jan

Jan - evidently it isn't oilcloth. Here is what it says...
CHALKBOARDÂ FABRIC
Color(s): Black. Width: 47.5". Encourage creative doodling by kids or adults! This lightweight and erasable material can be sponged clean with water to renew (grease will spot). Material is heavier than oilcloth but still flexible, and can also be used as a chalkboard.

Wow! Thanks for telling me grandma bonnie! The site I went to was habermann's & had the placemats & you could see the fabric. it is similar to oilcloth in looks but more silky. Will have to see if JoAnne's has it. GF has 2 young grandkids-nice xmas gift if not too expensive. Good Luck with your project ddb. Would love to see a pic!! Jan

Thanks everybody for all of your information and help. When I do find it I just have to figure out how you do it since I don't sew. And I don't know the first thing about sewing on a machine. Oh boy! I'm better off if I'm shown since I'm a very visual person. I need all the luck I can get...LOL