Try this great way to practice missing addends. Start with a number of snowballs, you decide how many. Have everyone hide their eyes, and you take some away (slide them under a cup, into a hat or a mitten). When they open their eyes, have students count how many they see. Then let them tell you how many must be hidden. Don't forget to ask them how they figured that out. When you are ready to record your games (and start writing number sentences) stop by my blog and pick up this free recording sheet.
or this one to help with "math talk"
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