Mamie Tice shared this great idea in her CAMT session. This lesson is a great way to teach young children about portion size in a hands on and meaningful way. You could use this idea with a unit on food and nutrition or a study on measurement.
Download several copies of the book "A Serving of Food is Fun". I have included the downloads in this post for your convenience. You can find the downloads on the Texas Department of Agriculture Site.
A Serving of Fun_Eng
A Serving of Fun_Span
Put together a basket of the items that represent the serving sizes of food we need each day. After reading through the book with students, have them work in small groups to explore the book and the size of the items in the basket. Encourage them to make comparisons and share what they learned.