In 2nd grade, students will build on last year's work and gain important new skills. One of the most important outcome for this year is to add and subtract two-digit numbers quickly and accurately. Students need a solid conceptual understanding of place value to do this. Another important skills in 2nd grade is to understand what the digits mean in three-digit number such as 915 (for example 915 is 9 hundreds, 1 tens, and 5 ones). Students also build expertise with solving addition and subtraction word problems. Of great significance is the skill of mastering addition and subtraction facts through the 12's. This of particular importance since in grade 3 multiplication and division facts need to be mastered.