This introductory chapter will review the number sense and place value topics covered in 1st grade. The chapter begins with modeling numbers in base 10 format (up to 20), counting and number patterns, and writing out a number using tens and ones (including pictures). This also includes the strategies of counting on and counting back. Students will then be able to identify whether a number is even or odd (depending on the ones place). Evens are identified by making partner cubes, and seeing if there are pairs or leftovers (odds). Students then review adding doubles facts, as well as a doubles plus/minus one fact. Next, students will show their understanding of place value by breaking numbers down into tens and ones and showing this through pictures in base ten form. They will choose whether a number is in the tens or ones place, and the value of those digits (symbols used in the numeration system). When determining a number's value, students will also be able to connect numbers into expanded form (stretched out) into 111=100+10+1. Students will practice the different ways to write numbers in standard form, expanded form, word form, and base 10 form. Students will also practice skip counting backward and forward by 1's, 5's, and 10's, and number patterns with hundreds, tens, and ones.