R.Y.
My 4 year old has some straw cups made by Munchkin with Backyardigans characters on them (other cartoons are available too). They don't leak because there is a valve in the straw. Also the top folds down and covers the straw. The only problem I have is if they ever get lost with milk or juice in them they are very hard to clean out, especially the straw and valve parts. I have some of the cheap take and toss straw cups. You have to put the lid on first and then put the straw through, otherwise the liquid squirts out the straw when you close the lid with the straw in place.