Children's Pitch Matching, Vocal Range, and Developmentally Appropriate Practice.

Kim, Jinyoung

Abstract. In this article, literature and research were reviewed to obtain general descriptions of children's musical development, especially their pitch-matching accuracy and vocal range, and what is considered to be developmentally appropriate practice (DAP). The factors affecting children's pitch-matching accuracy and vocal range were investigated and categorized into internal and external influences. The findings were discussed in terms of children's development and teachers' practice in the early childhood education setting. Children's musical development should be considered in a dynamic way. What we call "developmental knowledge" can be biased by how we define development and what we measure, and it may limit teachers' practice and children's authentic development accordingly.

Music is regarded as one of the important curricular components in early childhood education. However, early childhood educators do not seem to be as familiar with research findings concerning children's musical development as they are with research in other areas of child development. Consequently, the results of research studies concerning children's musical development do not affect early childhood practice, nor have they been able to raise debatable issues or lead to appropriate discussions for early childhood education. As an early childhood educator who is interested in children's music, this author cannot help but re-evaluate whether what we call children's musical development reflects developmentally appropriate practice (Bredekamp, 1987) for musical activities in early childhood education settings. This article reconsiders children's pitch-matching accuracy and vocal range, because pitch-matching ability is one aspect of musical development needed for singing, which is the most common musical activit y in early childhood education settings.

The following example will give a global view of the scope of this study. We often hear children make sounds (such as sirens). When they make the sounds of a siren, their voices go up to higher pitch than they use in singing. We also find that when children imitate instruments from tapes or radio, their voices also are higher than their usual singing pitch level. However, a lot of research has proven that children's vocal range and pitch-matching accuracy is limited. Consequently, many textbooks say that "D above middle C to A is the comfortable pitch range for children to sing" and so forth (e.g., Greenberg, 1979). Is there any error in these research studies? Or is there a large developmental domain that has not been studied by research protocols? How should early childhood teachers deal with this difference in their practice?

This article will study the interest in children's pitch-matching accuracy and vocal range in four parts: First, literature and research will be reviewed to give a general description about children's pitch-matching accuracy and vocal range, and to describe DAP singing activities. The second part will investigate factors that influence children's pitch. These factors will be categorized into internal influences, such as age and gender, and into external influences, such as modeling, tasks, and instruction. In the third section, the findings of the previous sections will be discussed in terms of children's development and teachers' practice in early childhood education settings. Further studies will be suggested in the final section and the limitations of this study will be considered.

Children's Musical Developmental Level

Children's Pitch-Matching Accuracy and Vocal Range

Pitch refers to the highness or lowness of a musical sound. Pitch-matching accuracy can be defined as the ability to match musical sounds of certain highness or lowness. Vocal range is the distance between the highest and lowest notes the voice can match (McDonald & Simmons, 1989). It has been said that pitch-matching accuracy and vocal range are highly correlated (Buckton, 1977; Wassum, 1979). In other words, children can match pitch well within their vocal range; vocal range is the absolute limit of pitch-matching ability each child can achieve.

Studies reveal that most preschool children have limited vocal range, from middle C to C++, which is one octave higher than middle C (Buckton, 1977; Drexler, 1938; Flowers & Dunne-Sousa, 1990; Hattwick, 1933; Jersild & Bientock, 1931,1934; Lyon, 1993; Moore, 1991), and that there is general growth in range both upwards and downwards as children mature (Welch, 1979). In Flowers & Dunne-Sousa's (1990) study, 3-to 5-year-old children were tested in singing a self chosen song, singing a taught song, and echoing 20 short pitch patterns. They found that older children sing a song with less modulation. In other words, older children were able to match a pitch more accurately. Welch (1979) studied major research findings related to vocal range and concluded that children's vocal range increases with age.

Singing

Some researchers believe that children's singing range is more limited than the vocal range in their natural sound making (Buckton, 1977; Flowers & Dunne-Sousa, 1990; Moore, 1991). Since children's singing range is limited, it has been suggested that children's limited range should be considered when teachers plan singing activities. The suggested singing range is between D and A above middle C.

What, then, is the relationship between singing and children's vocal range or pitch-matching accuracy? It is said that if we do not consider children's pitch-matching ability, it may contribute to children's poor pitch singing and vocal problems (Greenberg, 1979; Kuhn, Wachaus, Moore, & Panthe, 1979; Wassum, 1979; Welch, 1979). Because most singing activities are done in a group, teachers should be keenly aware of children's average ability to produce given pitches, even though there may be individual differences (Greenberg, 1979; Kuhn et al., 1979; Moore, 1991). Greenberg (1979) argued that one common problem with young children singing in groups is that some adults do not begin the song on a pitch that is comfortable for the majority of the children.

Our knowledge about children's pitch-matching accuracy and vocal range is from the results of the research that studied the factors influencing children's pitch-matching. These factors can be categorized into two groups: internal and external influences.

Influences on Children's Pitch-Matching

Accuracy and Vocal Range

Internal Influences

Age. Children's pitch-matching accuracy and vocal range are significantly related to age. Many researchers have investigated the age factor when analyzing children's musical ability (Buckton, 1977; Cooper, 1992; Geringer, 1983; Goetze & Horri, 1989; Gould, 1969; Green, 1989; Ramsey, 1981; Wilson, 1971). External influences could not be controlled, since the subjects of these studies were in school settings where the children could get musical instruction. Therefore, we must consider the age factor without regard to external influences, which will be considered in the following section.

Gender. While some of the research showed that there is no significant difference in pitch-matching accuracy or vocal range between different boys and girls (Apfelstadt, 1983, 1984; Cooper, 1992; Rutkowski, 1989; Smale, 1987; Tatem, 1990; Wassum, 1979), others reported differences with regard to gender. Prominent among this research are findings showing that girls sang more on pitch than boys (Goetze, 1986; Green, 1993; Stauffer, 1985; Wilson, 1971).

External Influences

Even though pitch-matching accuracy and vocal range are considered part of physical development, and hence require maturity, these skills also are influenced by environment. For instance, children who are exposed to a richer musical environment show a greater and earlier ability to carry a melody than those whose musical environments are poorer (Drexler, 1938). This raises the question: What kind of environment most positively affects children's pitch-matching accuracy and vocal range, and how should it be provided?

Modeling and accompaniment. Modeling or accompaniment can affect children's pitch-matching accuracy and vocal range, although the research results are too varied to generalize the extent of this influence. Some studies reported that children were more easily able to match a pitch presented by a female voice rather than a male voice (Green, 1989; Sims, Moore, & Kuhn, 1982). Others reported that children who could match pitch with one model could generally match pitch with the other (Small & McCachern, 1983).

Research about accompanying songs also showed different results. One finding was that children sang more accurately individually than either with the vocal modeling or when in a group (Goetze, 1986; Goetze & Horii, 1989; Smale, 1987). Another result was that children sang more accurately when singing in unison with their peers than when singing individually (Green, 1993).

There were also different results in the research about the influence of accompanying instruments. Some research showed that the influence of instrumental accompaniment was not significant (Atterbury & Silcox, 1993; Hale, 1978). However, other research demonstrated musical instruments having an effect. The effect of a musical instrument can be considered in terms of its timbre and melodic or harmonic effects. For instance, some research shows that children sing significantly better with types of vocal timbre or sounds that are similar to their own voices (Green, 1989; Hermanson, 1971; Lyon, 1993; Tatem, 1990). Some research showed that children sing better with melodic replication or traditional tonal harmonic accompaniment than with either chromatic or dissonant harmonic accompaniment (Stauffer, 1985; Sterling, 1984). This may be because accompaniment can distract children and hinder the main melody.

Task. Another external influence is the task of singing. What can affect children's vocal range or ability to match a pitch? Some studies showed the influence of song lyrics. For instance, a song without words was performed better than a song with words (Goetze, 1986; Levinowitz, 1989), even though other research showed no significant difference between singing with or without words (Smale, 1987). Young children may be distracted by the orderly arrangement of the words of a song learned by rote.

Another kind of study was done to consider pitch patterns in children's pitch matching. In Flowers and Dunne-Sousa's (1990) study, children could match higher pitches when they echoed the pitch patterns than when they sang a song. Those authors found that the children took more risks in echoing the pitch patterns, and so the vocal range was greater, even though they did not extend their voices on the higher pitches when they sang.

Instruction. Most of the studies on instructional effects focused on children's pitch-matching accuracy, and most of the results showed a positive effect for children's pitch matching (Apfelstadt, 1983, 1984; Buckton, 1977; Gould, 1969). One interesting study is Apfelstadt's (1983), in which he studied the effect of vocal instruction designed to promote melodic perception through visual and kinesthetic reinforcement, as well as to provide instruction, primarily through imitation. He compared these two types of instruction with traditional instruction, and found, with both types, a significant difference in vocal pitch-matching accuracy. This study showed that instruction could stimulate senses other than aural ones; showing pictures or feeling textures, for example.

Discussion

Studies and Limitations

Internal influences. As described earlier, early childhood educators may have been correct in depending on maturationists' views to consider children's pitch-matching ability and vocal range. Relying on the maturationist perspective, however, has led early childhood educators into a narrow view of education that emphasizes children's developmental stages and the practices congruent with those developmental leves. Early childhood teachers may consider children's limited vocal range when they plan singing activities, for instance.

Such an approach may underrepresent children's potential, however. Consider children's greater pitch-matching ability in their making sounds or singing songs during free play, for example. In addition, we cannot say that the results of the studies reflect the children's actual maturation level, because we cannot know those levels without considering external influences, especially if external elements influence children's pitch-matching ability or vocal range. By the same token, we do not know the children's potentials under external influences, because some research showed striking gains in children's pitch-matching ability with some instructional methods. We may still have limitations in developing instructional methods and in putting them into practice.

External influences. What might be the limitations of the studies regarding external influences? And, as this author has repeatedly asked, why cannot children's naturally achieved high pitch be evident in their singing? First, we have to think about modeling and accompanying for children's pitch-matching accuracy. Most studies measured children's pitch by observing their singing after modeling by experimenters or instruments. Children did better for brief melody patterns because they could just echo the sounds made by the experimenter. For whole songs, however, children could not keep the same pitch level. Flowers and Dunne-Sousa (1990) explain that children are more likely to open up their vocal ranges when modeling brief patterns than when they sing songs that demand the same range. It seems that the immediacy of hearing and responding to brief pitch patterns is less demanding than the complex self-monitoring over time that is required in singing a song. If singing requires more complex skills such as self -monitoring or memory, should we limit children's singing range or pitch-matching ability based on their singing ability? At the very least, it may be worth testing any possible effect of modeling or accompaniment on children's pitch-matching accuracy so that we can ascertain their maximum singing ability. If children's short memory hinders their ability to match what the experimenter models, educators could devise a method for accompanying children's songs that does not distract their voices to help them keep their pitch.

Second, the songs used for the studies may have limitations. Some studies showed that the children performed better in the song without words than the song with words (Goetze, 1986; Levinowitz, 1989). We may still determine children's pitch-level by the results of the studies using songs with words. Many researchers seem to agree that young children may be distracted by the orderly arrangement of the words of rote song. If children's pitch-matching ability is different in the song with words than in the song without words, should we determine children's developmental level only from the song with words? How about having different types of children's songs such as songs with imaginative sounds like sirens? Flowers and Dunne-Sousa (1990) suggested that learning to use the higher pitches through echoing exercises might help children to develop a singing range that would allow melodic contours to be more accurately produced. By the same token, if children can use higher pitches in different types of songs, it mi ght help the child to develop a singing range in songs with words.

Third, we should think about the effect of the length of the instructional period. Most of the studies this author researched acknowledged those limitations. For instance, Buckton (1977) acknowledged that 8 weeks of instruction, 10 hours total, is not enough to significantly change children's pitch. Hattwick's (1933) study did not find such significant differences in children's pitch matching and vocal range after 24 group practice sessions. After 48 group practice sessions on one song, however, the pitch range of preschool children was significantly wider than the pitch level in their voluntary song in the first periods. A large number of the children who could sing parts of songs correctly can manage to sing a whole song if they have been sufficiently encouraged to do so (Moog, 1976). If children could echo a part of a song as a melodic pattern with wider vocal range than a whole song, it might also be possible for the children to sing with the same vocal range when they had been given sufficient encourage ment and practice.

What Is Developmentally Appropriate Practice for Children's Singing?

Actual developmental level. Considering our knowledge and the limitation of the current studies on children's pitch-matching abilities, we must reconsider what is developmentally appropriate practice in children's singing. Early childhood educators have often referred to theories of developmental stages (such as Piaget's) to make decisions regarding readiness. Piaget's theories have been popularized as a universal set of cognitive categories of thought and development (Confrey, 1991). Many teachers think they are supposed to wait until children reach a certain stage before they are able to learn something. This view also has been applied to children's singing. For example, Greenberg (1979) classified children's vocalization into five stages:

Stage I: The first vocalization (birth to 3 months).

Stage II: Experimentation and sound imitation (3 months to 1 year and 6 months).

Stage III: Approximation of singing (1 year and 6 months to 3 years).

Stage IV: Singing accuracy in limited range (3 to 4 years).

Stage V: Singing accuracy with expanded range (after 4 years).

Children in stage IV can sing tunes within the limited range of D to G above middle C. The children's vocal range is expanded to A, B, or C above middle C in stage V. Greenberg believes that it is not until age 5 or later that a typical child will be able to reach the higher tones with much accuracy, due to an inability to control the physical mechanism needed to produce these tones. Teachers should begin to teach children at this age many songs with a limited tonal range and with catchy tunes or tonal patterns, reinforcing the pitches on the piano or with bell-like instruments.

However, these theories of developmental stages have raised other questions about limitations in applying DAP. First of all, it limits teachers' thinking to certain stereotypes of children's developmental levels, and therefore limits their practice. This author has rarely observed teachers letting children make higher pitches than at the level assumed to be developmentally within their singing range. Instead, many teachers use their own comfortable singing range, which is often rather too low for children. If there is no significant difference in the effect of this restricted song range on the children's use of their singing voice (Rutkowski, 1989), is there any reason to stick to the restricted song range believed to be appropriate to the children's developmental stage? Second, from the research review, we have found that children's developmental level is not static, but rather is dynamic, affected by external influences such as instruction. If children's developmental characteristics are affected by extern al influences, we should define children's developmental level in away that incorporates all relevant influences.

Zone of proximal development (ZPD). Zone of Proximal Development is "the distance between the actual developmental level as determined by independent problem solving and the level of potential development as determined through problem solving under adult guidance or in collaboration with more capable peers" (Vygotsky, 1978, p. 86). In other words, ZPD includes the functions that have not yet matured but are in the process of maturation, and so they can be helped by competent adults or peers. Therefore, we may assume that the internalization of social forms of regulation is much more than the acquisition of self-control through inner speech (Wozniak, 1987). The ZPD's emphasis on the role of instruction in children's development may be contrasted to Piaget's theory of unidirectional progress through stages. It would be a mistake to overemphasize the child as other-directed. When we interpret DAP, however, we may need to consider intersubjectivity. It is also true that child development cannot be understood wit hout reference to the institutional and interpersonal milieu in which the child is embedded (Tudge & Winterhoff, 1993). The notion of ZPD gives us a new formula; namely, that the only good learning is that which is in advance of development, and that learning oriented toward developmental levels that have already been reached is ineffective.

ZPD often has been used to explain functions in relation to domains outside of cognition. Therefore, ZPD could help explain the gap between children's natural pitch and singing pitch. If children can imitate only pitches within their developmental level (Vygotsky, 1978), then might it be true that children's natural pitch, made by imitating adults' pitch patterns or natural sounds is, ipso facto, in their developmental level?

In the research review, however, this author found some questions in applying the definition of ZPD. First, is the assistance of "competent others" always helpful? It is always possible that such help may not work well in certain cases. For instance, some studies show that modeling or accompanying may not necessarily help children to match pitch. In other words, even though teachers are more competent than the children they teach, teachers' help is helpful only when it is focused appropriately. So, when we define ZPD, we cannot just assume that competent adults always improve children's development.

Second, is children's ZPD in musical development domain-specific? Children may show certain behaviors or developmental characteristics in one task or situation, but not in all tasks or situations. For example, children could make higher pitches in a melodic pattern or natural sounds, but not in a complete song (Buckton, 1977; Flowers & Dunne-Sousa, 1990). Should children's possible vocal range then be considered as the potential limit of vocal range for singing? Apfelstadt's (1983) study demonstrates the effect of vocal instruction designed to promote melodic perception through visual and kinesthetic reinforcement on children's pitch-pattern accuracy. Such considerations suggest the need for more elaboration about instruction in the ZPD, and acknowledgment that development can be improved not only by competent adults' help, but also through stimulation in other domains.

Suggestions for Further Studies

This author has tried to find a relationship between what is known from the research about children's pitch-matching accuracy and vocal range, and what we have defined as DAP; she has tried to apply this knowledge to early childhood education practice. However, the philosophical question of why pitch-matching ability is important should be understood as a component of a value or belief system, which is affected by cultural context. Many people think that music for children has meaning only or largely for their aesthetic development, making the issue of pitch matching unimportant. In fact, this author has observed many early childhood classroom teachers in the U.S. who do not care about pitch. This author acknowledges that the assumption of this paper--that pitch-matching accuracy is an important development in children's singing--reflects her cultural bias and personal belief. Therefore, the following suggestions for further studies are given to researchers who also may be interested in and/or believe in the importance of children's pitch-matching accuracy and vocal range:

First, we need to study children's spontaneous musical utterances to evaluate vocal range, complexity, and tonal modulations. Inmost of the studies, children were asked to sing with vocal or instrumental accompaniment, or to echo pitch patterns in a given tune (Atterbury & Silcox, 1993; Flowers & Dunne-Sousa, 1990; Goetze, 1986). Even though some studies included children's pitch matching in their self-chosen songs, however, children's vocal range or pitch-matching accuracy in the same song was not compared in terms of the context (such as their singing in a given tune) or in terms of spontaneous musical utterance.

Second, children's pitch-matching accuracy and vocal range can be studied in relationship to the words of children's songs. Many studies have focused on the effect of the words on children's pitch-matching ability (Goetze, 1986; Levinowitz, 1989; Smale, 1987). These studies have compared children's pitch-matching ability when they sing a song with words with their pitch-matching ability when they sing with neutral syllables such as "la-la" or "bum-bum." However, the effect of onomatopoeic sounds (such as a siren) was not investigated in any study. If children can reach a higher pitch when they imitate sounds such as a siren, their pitch-matching ability might also differ in their singing a song while imitating words as a part of the song.

Third, we need studies about children's tonal memory to determine when the length of a song becomes problematic. As shown in Flowers & Dunne-Sousa's study (1990), for brief melody patterns, children, could do better because they could just echo the experimenter's sounds. For whole songs, however, children could not keep the same pitch level. If singing requires more complex skills (such as self-monitoring or memory), we need to study children's tonal memory in relation to the length of a song, and to children's pitch-matching accuracy and vocal range in their singing.

Fourth, we need more studies to investigate the effect of instruction. As Flowers and Dunne-Sousa's study (1990) proved, children were more likely to open up their vocal ranges when modeling brief patterns than when singing songs that demand the same range. Those researchers suggested that learning to use higher pitches through echoing exercises may help children develop a wider range in singing. By the same token, it may be possible that children can learn to use higher pitches through imitating natural sounds. We should study the effects of echoing exercises or imitating natural sounds on children's pitch-matching ability and vocal range. The results can be compared with the effect of musical instruction that focuses more on restricted vocal range.

Fifth, we need to investigate interaction effects among influential factors. Most studies of children's pitch matching have investigated the effect of one external influence, such as a different task or instruction, on some interaction effects between external influence and internal factors, such as age or gender. However, there seem to be some confusion in these studies. For example, when we get a conclusion that children can match a higher pitch in a melodic pattern than in a song, we cannot determine whether it is because of the length, or the phrase itself, or others' help that affects children's pitch-matching ability. Therefore, there needs to be more studies to investigate interaction effects among external influences, such as word type, context, and vocal assistance.

Conclusion

This article investigated children's pitch-matching ability and vocal range from the perspective of an early childhood educator applying developmental theories from research into developmentally appropriate practice in early childhood education.

Our knowledge of children's pitch matching accuracy and vocal range is very limited and static. This knowledge often has been applied in singing activities that emphasize children's readiness for their development. Restricted range is not always developmentally appropriate for children's singing. Rather, the relationship between children's pitch-matching accuracy and singing should be considered in a dynamic way. As suggested in the former section, there may be some ways in which we limit children's potential development by limiting the definition of developmental level and developmentally appropriate practice.

We still need to answer the questions "How do we see children's development?" and "How does the knowledge about children's development affect early childhood curriculum, including children's learning and teachers' instruction?" What is called developmental knowledge is already biased by how we define development and what we want to measure and so it may limit children's authentic development. This limited knowledge about children's development also can give us an overly narrow view of the curriculum. Therefore, we need more research to expand on current knowledge and to encourage thought about more possibilities.

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