This website has a TON of cheap decorations, wedding stuff, crafts, etc. Catering you dessert section in all blue sweets is a great way to include your wedding theme colour of blue into your food choices!
Disney Frozen Ombre Rice Krispie Treats - we made these beautiful Ombre Rice Krispie Treats for our Disney Frozen Birthday Party. They were a big hit and would be pretty in any color combination or for any special occasion or party. For more amazing Froze
Take home treats or for dessert, I love how these wands are standing in jelly beans (I'm sure a base of blue tack would help hold them! You could also provide undecorated cookies on sticks, and pre-filled bags of icing, for the little ones to decorate.