This whole scenario was all too common in our house with my 23 month old twins. The twins love homemade smoothies and I love offering them, but unfortunately thick smoothies don't work well in a sippy cup. They require a cup with a straw and a lid. However, until recently that opened up a multitude of potential drink play that had me ready to just stop giving them smoothies altogether. With twins, one sees the other doing something and just has to do it too; meaning one drink spilled becomes two drinks spilled in short time.
However, a clever mommy has a solution that I found works quite well (or as she prefers to call it "a straw-lution"). This mommy made a straw that goes in cups and other items, but can't be removed by your little ones due to a one way anchor system. These special straws are sold 12 to a pack in 4 colors; pink blue, yellow, and green for $4.99 and I was sent a yellow pack for my review. I was impressed to find out that they are BPA free, dishwasher safe, reusable and/or tossable.
According to the manufacture, the Straw-lution Straw is appropriate for ages nine months on up. I found it really does minimize the mess associated with eating pre-packaged small cup foods, such as baby food, applesauce, pudding, yogurt, and even juice boxes. Additionally, it's the perfect height to work with those wash and toss cup and lid sets as well as child size drinks in food establishments.