Get them to drink MILK!
When my daughter was two I would tell her plain milk was vanilla milk and she excitedly would drink her milk. She is now six and getting her to drink plain milk is a challenge since she has now had chocolate and strawberry milk. I have found a new way though to get her to drink her milk without adding the syrup or powder to it that contains a lot of sugar. My newest solution is to add a splash of flavored coffee creamer to her milk. She LOVES it! They are low in fat, sodium, carbs etc and add the extra flavor. What's also great is you can buy them for next to nothing if you use the coupons that are out these days. A lot of stores double coupons that are less than a dollar so along with a sale price on these creamers they are super inexpensive.