Hi Sarah,
I'm from UK originally but am now in France, also with two little ones although my smallest is coming up for 4 now...
Do you have a little quilt shop locally, if so perhaps sign up for a class, or ask their advice. I'd start with a little charm pack quilt or a strip piece quilt, perhaps your kids have a favourite character that you could make a panel quilt...Ive still got to make my DS a digger quilt out of a panel i've had around but he's coming up for 7 so I've missed the boat a bit :O( perhaps your son's would like it. I'd be happy to send you the fabric as a fabric angel, let me know :O)