The simple answer is a pancake is a crepe, only thicker. The batter to make both is almost the same, just add a little more milk or water for a thinner crepe batter. Then give some thought to what you are going to fill them with. I tend to fill pancakes with savoury fillings, things like vegetables in cheese sauce, creamy chicken and mushroom, or savoury mince as the extra thickness of a pancake makes it easier to wrap and fill this type of hot filling, without tearing.
Crepes are just perfect for sweet fillings, try filling them with fruit for a light after dinner dessert or a quick midday snack.
But whether you choose a pancake or a crepe, the number of fillings are endless and as they are such fun to make you might even get the kids to help you make them.