## Better than Average

### MAdele CarsonSanta Rosa District Schools

#### Description

Students use baseball cards to understand averages, decimals to thousandths, and the real-world use of math.

#### Objectives

The student reads, writes, and identifies decimals through thousandths.

The student compares and orders commonly used fractions, percents, and decimals to thousandths using concrete materials, number lines, drawings, and numerals.

The student translates problem situations into diagrams, models, and numerals using whole numbers, fractions, mixed numbers, decimals, and percents.

#### Materials

-Overhead and pen or board
-Common baseball cards
-Overhead calculator (optional)
-Calculators
-Pencils and paper

#### Preparations

1.Obtain common baseball cards (those that make up the majority of a package). Card stores sell 'commons' for pennies in 'common bins'. Students may also have commons at home that they will bring in for the lesson.
2. Obtain (ideally) a class-set of calculators or as many as possible and a Cal-cu-view (overhead calculator) if available.
3. Review the basic use of the calculator and its functions.
4. Review the use of averaging (such as in grades).

#### Procedures

1. Following the review of the use of calculators and figuring out an average, introduce the use of averages in baseball.

2. Using a player's card, demonstrate how baseball players' batting averages are obtained. Remind students that 1.000 is perfect (thus the term 'batting a 1000') and that players that have that average usually only have it, at the most, for 1 or 2 at bats. Use the fraction of 1/1 to show an average of 1.000. When a player makes another hit, he will be 2/2 and still batting 1.000. If he fails to make a hit in his third at bat, he'll have 2 hits out of 3 at bats, thus 2/3 which equals .666. With his next at bat (4) without a hit, he'll be 2/4 or .500. Remind students that a fraction is a division problem and that by dividing the denominator (the number of at bats) into the numerator (the number of hits), we get a decimal which is the player's batting average.

3. While either writing on the board or the overhead, or using an overhead calculator, demonstrate how a player with 55 hits in 237 at bats would have a batting average of .232.

4. Hand out the common cards and explain the abbreviations on the card back. Explain that AB stands for at bats; H stands for hits; and AVG is the batting average. AVG = H/AB

5. The students 'check' the averages on the cards by dividing the at bats by the number of hits for each year of the player's career.

6. After checking for understanding, have the students add the season averages of a player and divide by the number of seasons played to get his career average.

7. Students can trade cards and 'check' another player's averages.

#### Assessments

Using the statistics from the back of a baseball card, list a random player's at bats and hits. The students, using the calculator, will figure out the player's average for each season as well as the career average. Check the students' answers to see that they understand the concept. This is a formative assessment. Students who don't grasp the concept or the skills needed, should have additional time and instructions.

#### Extensions

Students can use a plastic bat and ball and calculate their own batting averages in ten pitches. Be sure to observe safety standards. This activity should take place outside.

#### Web Links

Web supplement for Better than Average
Baseball Math