A fun way to practice numbers and saying how much something costs: have your students play "The Price is Right!" in FRENCH!
This powerpoint includes random vocabulary and items that students will guess the prices of with a partner (or two). I had my students write on a separate piece of paper the item #, the item, and "il/elle coûte", based off of the item's definite article. There are 13 items total.
I introduced each item one by one and gave students time to deliberate with their partners the cost. After all 13 of the items were completed, we went item by item and each group told their classmates their guess in French!