Have you ever had a group of students who could SAY the numbers, and idenify some, but couldn't actually look at all of the first 20 numbers and put them in order?
One of the activities I planned to fix this used these number cards. First we shuffled the numbers on our desk and I called out each number in order to find. Then we shuffled again and I called them out of order. Then, I handed out the construction paper and we glued them in order.
It helped some!