# Subtraction Facts

Addition and subtraction facts are some of the most important skills children will tackle in first grade. Strong addition skills will be a big help to kids who are learning to subtract, but subtraction does carry with it several unique challenges for kids, and some children take years to master it fully.

### What Kids Need to Learn

• Subtraction Concepts: what happens to a group of numbers when some are taken away
• Subtraction Strategies: a bridge between understanding subtraction concepts and memorizing math facts
• Memorize: subtraction facts up to 20

### Putting the Math in Context

In kindergarten, children were introduced to the concept of subtraction and worked with counters and other manipulatives to show simple subtraction problems. They learned terms like "take away", "minus", and "left over", and worked with the symbols for + and -.

In first grade, children will learn subtraction facts up to 20. They will work more with written numbers, though they will still get plenty of practice working with counters and objects. They will learn subtraction strategies to help them solve problems more quickly and accurately. They will be expected to memorize the facts up to 20 so they know them fluently. Near the end of the year, kids will work with larger numbers and learn how to regroup (many of us called this skill "borrowing" when we were kids).

In second grade, kids will become more fluent with subtraction, and should have their facts to 20 memorized. Some second graders will still be grappling with subtraction concepts. They will work more extensively with regrouping, and near the end of the year will subtract 3-digit numbers with decimals, as are often used in working with money.

### Why It's Important

It hardly needs to be said, but subtraction is one of the most important math skills kids will need, right up there with addition. Subtraction is essential for all kinds of computation, and a solid understanding of subtraction concepts and skills will also be foundational for division and fractions.

### Math Challenges Kids Might Face

• Subtraction is a harder concept than addition. In addition, counting moves upward; you start with one quantity and keep counting as you add on to it. Subtraction is trickier. You start with a larger number and take some away. To do this, kids either have to count backwards or start with the smaller number and count up, which is counter-intuitive to the concept of taking something away.
• Some children have trouble memorizing. This year, kids will be challenged to remember their subtraction and addition facts up to 20. This is a pretty big order, especially if kids are not yet secure in their understanding of the math concepts.
• Children can become overly dependent on "crutches" for subtraction. They may become so used to using a number line that they are unable to function without it. Others may use only one strategy, such as counting backwards from the higher number, or they may be lost without enough objects or fingers to solve subtraction problems. If relied on too much, these can interfere with kids becoming fast and fluent in their subtraction facts.

### How to Help With the Math

1. Lay a super strong groundwork of learning addition, and learning it well. Addition and subtraction are very closely related, and the stronger a child's addition skills, the easier it will be for him to master subtraction facts.
2. Deliberately point out connections between addition and subtraction problems. One of the best ways to do this is by spending plenty of time on fact families, which make the relationship between addition and subtraction very clear.
3. Give lots of practice with counters, math stories, objects, and any activities that let kids have hands-on practice with subtraction facts. The more they use these concepts in real life, the greater their understanding will be when working with numbers.
4. Use drill and memorization to make kids' knowledge of subtraction facts automatic. Once they have a grasp of the general concept of subtraction, focus on building accuracy and speed through activities, games, and lots and lots of practice. (TIP: using a timer can make learning math facts a lot more fun!)
5. As with all deep learning, choose activities that use children's whole bodies. Different kids learn in different ways. Drill subtraction facts while jumping rope, make it into a clapping game, listen to a CD with subtraction songs, use flash cards, play memory games. Find what works for your kids and teach to their learning styles.

### Whiz Kids

To challenge kids who are ahead of their peers, try:

• timing them on their subtraction facts and encouraging them to beat their previous times
• doing subtraction activities with larger numbers
• letting quick learners help slower learners
• having supplementary worksheets or simple practice activities available for when kids finish more quickly