I love to teach my students the strategy of finding tens when they are adding groups of numberes. This lesson really gives them a lot of practice with it. Each student receives a sample page of the "phonebook" and a worksheet. The students should look at each phone numer and see what tens they can and complete the worksheet. This is a great stategy lesson.
I am a blended special education teacher and have taught at variety of grade levels. Most of my materials are designed to work for a variety of grade levels as I have often worked with more than one grade level at a time.