When we went a few weeks ago with DS(2.5) I brought with me a bunch of the disposable sippy cups. At the TS's you don't need any cups, they just get a kids cup. At many of the CS's my DS would drink a small sized Quick chocolate milk on his own with a straw. I used the disable ones to fill up with leftovers. I could then chuck them and not worry about losing expensive sippy cups.