I Don't want using sugar for my toddlers snacks, but he doesn't like honey. What is the best subtitute for sweet except honey for making cake/ cookie?

You can consider using Stevia. Stevia is perhaps unique among food ingredients because it's most valued for what it doesn't do. It doesn't add calories. Unlike other sugar substitutes, stevia is derived from a plant. http://www.livescience.com/39601-stevia-facts-safety.html Or you can also use fruits to enhance the natural sweetness for cakes/cookies. Chocolate is also another choice if you intend to avoid sugar for the bakes.