I created this calendar to help document what my girls are eating. It's pretty basic and I'll have to learn how much each serving is but I think this is a good start. For example one toddler serving of fruit is about 1-2 T mashed fruit. I can imagine a banana being about 2 fruit servings because if I mashed it I'm guessing I would get at least 4 T. of mashed fruit. We'll see how it goes. You're welcome to use the image or let me know and I can email you the real document. Please let me know what you do to help with your kids eating habits. I would love to know any tricks you have in adding nutritional foods or knowing how much a serving size is.
Here are a couple links that may help you guys out...the first one gives a pretty good guide for how big a serving size is for a toddler. The second shows you the food groups and if you click on each one it goes into detail about it. i.e. half of your grains each day should be whole grains (whole wheat, oatmeal, etc.)