age of entry, preschool experience, and sex as antecedents of academic readiness in kindergarten

Early Childhood Research Quarterly, 7, 175-186 (1992)

Age of Entry, Preschool Experience, and Sex as Antecedents of Academic Readiness

in Kindergarten

Dominic F. Gullo Christine B. Burton

University of Wisconsin-Milwaukee

Readiness, or preparing young children for the formal curriculum, is garnering much attention and controversy in the field of early childhood education. Many factors have been examined in efforts to determine what affects academic readiness. The purpose of this study was to examine the effects of children's age of entry, number of years of preschool, and sex on academic readiness at the end of kindergarten. A total of 4,539 children participated in the study. Of these, 104 children started public school at age 3 (K3), 1,234 started school at age 4 (I(4), and 3,201 started at age 5 (KS). At-risk status was determined using the Cooperative Preschool Inventory (Caldwell, 1974), and first-grade readiness was determined using the Metro- politan Readiness Test (MRT; Nurss & McGauvran, 1974). Controlling for risk status, regression analysis revealed that age of entry and number of years of preschool accounted for a significant amount of the variance, while sex did not. Analyses of covariance indicated that children who entered the public school preschool program at K3 or I(4 scored significantly higher on the MRT than children who entered at KS. The findings also indicated that if children were the youngest in their class they did not score as high as their older counterparts in the K4 and K5 cohorts. However, no difference was found on achievement scores between the oldest and the youngest for the K3 cohort.

M u c h a t t en t ion and con t rove r sy is cur ren t ly focused on p repa r ing y o u n g ch i ldren for f o rma l school curr icula . A c c o r d i n g to A l e x a n d e r and Entwis le (1988), ear ly school ach ievement , or academic readiness , is an i m p o r t a n t p r ed i c to r o f a ch i ld ' s successful a d a p t a t i o n to school rou t ine , which has long- t e rm consequences for fu tu re cogni t ive and af fec t ive deve lopment .

This study was funded in part by a grant to the first author from Binney and Smith, Inc. Correspondence and requests for reprints should be sent to Dominic F. Guilo, University of

Wisconsin-Milwaukee, P.O. Box 413, Enderis Hall 310, Milwaukee, WI 53201.

175

176 Gullo and Burton

Many factors have been examined in efforts to determine what affects academic readiness. These include the child's relative age of entry into formal schooling, prior preschool experience, risk factors such as economic poverty, and the child's sex. Yet most earlier studies have examined these factors in isolation or as they affect selected populations of children, rather than examining the interactive effects of these factors on academic readiness in the general population of young children (Goffin, 1989). The purpose of this study, therefore, was to examine the effects of children's age of entry, number of years in preschool, and sex on academic readiness by the end of kindergarten.

Academic readiness is determined by the child's ability to construct and reconstruct knowledge in a way that is consistent with the expectations of the school and the formal curriculum. As such, readiness is affected by both biological and experiential circumstances. In the present investigation, two biological factors (age and gender) and one experiential factor (prior preschool experience) were studied. The effects of these factors on academic readiness are discussed in the following sections.

The Child's Chronological and~or Developmental Age An important policy and practice issue facing the early childhood profes- sion is the effect of age on the child's ability to benefit from prekindergarten or kindergarten experiences. There are really two questions being asked with regard to the age issue. The first concerns the child's relative age within his or her grade cohort. The question being posed is: Do children who are older within grade benefit more from the school experience than children who are younger?

Traditionally in the United States, children have been of legal age to enter the public schools at age 5, when they typically enter a kindergarten class. A desired characteristic of the kindergarten curriculum is to be flexi- ble so that it will meet the developmental needs of individual children. Recently, there has been major concern that not all 5-year-olds are, in fact, "ready" for kindergarten (Uphoff & Gilmore, 1986). This is due primarily to the increased academic demands being placed on children by the kindergarten curriculum. In response to this, there is a widespread trend for states to raise their kindergarten entrance ages (Freeman, 1990). In addition, there are many individuals who advocate that children should enter school based on their developmental age rather than their chronological age (Uphoff & Gilmore, 1986). A central assumption of this position in that children should enter school based on their score on a test of developmental abilities. Children who do not score at a predetermined level are presumably in need of more time to mature. These children are either encouraged or required to wait another year before entering school.

The research findings regarding age of entry are clouded at best. While some studies show that the youngest children in an academic kindergarten

Antecedents of Readiness 177

do not fare as well as the older children (DiPasquale, Moule, & Flewelling, 1980; Karweit, 1988), others have demonstrated that the negative effects of being the youngest in the class disappear in later years (Kinard & Reinherz, 1986; Shepard & Smith, 1986). The difficulty with generalizing these findings is that entry age has typically been studied in isolation from other variables rather than in conjunction with other aspects of early education policy and practice.

Prior Preschool Experiences The second question concerning the age issue relates to the question of when children should, in general, begin school. In most states, the compulsory school entrance point is first grade, or 7 years of age. Preschool can thus be defined as those programs serving children prior to first grade, including kindergarten. As such, preschool education is becoming an increasingly common, yet variable, experience for American children.

Although attendance is mandatory in only a few states, kindergarten is now virtually a universal experience. It has been estimated that 95°70 to 97070 of eligible children in the United States attend kindergarten (Gullo, 1990; Sava, 1987). Public school programs serving children below the kindergarten level (i.e., 3- and 4-year-olds) are, by contrast, still in their infancy. While only approximately 8 states invested public funds in preschool programs for 3- and 4-year-olds one decade ago, 31 states had initiated such programs by 1989 (Mitchell, 1989). As one might assume, children who attend these programs will enter school at different readiness levels. This latter issue has emerged as a particularly sensitive policy concern, given data showing that while 67070 of children below kindergarten age from middle class homes attend some form of preschool, only 33070 of children from homes of economic poverty do so (National Association of State Boards of Education, 1988).

Research on the effects of varying preschool experiences has been somewhat limited to studying populations of children who are in need of inter- vention (Goffin, 1989) or to examining the different effects of specific curriculum models (Powell, 1987; Schweinhart, Weikart, &Larner, 1986). There are, therefore, significant limitations in our ability to generalize these findings. While there is much consensus among early childhood educators as to what constitutes appropriate classroom practice for preschool and kindergarten children (Bredekamp, 1987), there is little empirical evidence examining the effects of these practices on children who represent the nor- mative population characteristics.

The Child's Sex Along with age and prior preschool experiences, sex is a factor that may have important influences on a child's academic readiness. Because the majority of teachers at the early childhood level are females, and because


boys mature at a slower rate than girls, there has been concern that there may be a feminization of the curriculum for children during the early years in school, possibly leading to detrimental effects, especially for boys (Gullo, 1990; Gullo & Clements, 1984; Lee, 1973). Previous research has shown that sex differences at this level manifest themselves in many forms.

At the broadest level, cultural or societal expectations shape perfor- mance. Teachers and parents in the United States tend to expect girls to per- form better in reading, whereas those in other cultures believe boys would be better in reading (Lehr, 1982). These variations in expectations affect teacher-child interactions. For instance, teachers make more academic con- tacts and spend more cognitive time with girls in reading, which is associated with sex differences in end-of-the-year reading achievement (Fagot, 1973, Gullo, 1990; Gullo & Clements, 1984; Leinhardt, Sewald, & Engel, 1979). In kindergarten and first grade, ratings of academic achievement favor girls. This is true even when there are no initial (kindergarten) or final (end-of-first-grade) sex differences in actual achievement.

Although the child's sex is a biological trait, being a male or female inescapably leads to different physical and social experiences in one's environment. Thus, boys and girls construct knowledge differently. The above- mentioned studies have shown that the behavioral and social expectations of the school environment and the curriculum are more closely aligned to early feminine patterns of cognitive and social development. This, coupled with the differences in rates of maturation between boys and girls at this age, may put boys at a disadvantage, both academically and socially.

Taken together, then, the following research questions were explored in this investigation:

1. Controlling for cognitive level (risk status) at entry, what are the effects of age of entry, prior preschool experience, and sex on academic readiness at the end of kindergarten?

2. Controlling for risk, does academic readiness differ between children who are the oldest or the youngest in their class?

3. Controlling for risk, does academic readiness differ depending on the number of years of preschool children have experienced?

4. Controlling for risk, do boys and girls differ in academic readiness? 5. Are there interactions among the above variables?

METHOD

Subjects Subjects for the study attended pre-first-grade classes in a large urban school district. In addition to having preschool for special-needs children and for children from economic poverty (Head Start), the school district of- fers preschool classes for children at the 3-, 4-, and 5-year-old levels (K3,


K4, KS). Because of limited resources, the K3 and K4 children are chosen randomly by lottery from all interested families. K5 is offered for all children. In this study the children in the K3 group attended K3, K4, and K5 before first grade; the K4 group attended K4 and K5 before first grade; and the K5 group attended only K5 before first grade. There were 104 children in the K3 group (53 males, 51 females), 1,234 children in the K4 group (606 males, 628 females), and 3,201 children in the K5 group (1,623 males, 1,578 females). Children were not included in the study if they attended more than one district school before first grade, were in special classes, or were in a special school (i.e., bilingual, special curriculum). A total of 4,539 children participated in the study. None of the children attended preschool programs other than the public school. All teachers were degreed early-childhood educators.

The ethnic representation in the school system is 1.2°70 American Indian, 55.3°7o black, 3.0070 Asian, 8.8°7o Hispanic, 30.8°70 white, and 3.0o7o other groups. Fifty-eight percent of the children were eligible for free lunch.

Procedure

Age of Entry. Age was examined in two ways. For the regression analyses, age was viewed as a continuous variable (in months). For analyses of variance, age was viewed as a categorical variable using the following criteria to divide the children: (a) those who started kindergarten at 5 years, 6 months, or below; and (b) those who started kindergarten when they were older than 5 years, 6 months. This age division is consistent with that rec- ommended by advocates of delaying children's entrance into kindergarten if they are developmentally "too young" (e.g., Uphoff & Gilmore, 1986).

Risk. Children's "at-risk" status was assessed upon entering the public school K3, K4, or K5 program using the Cooperative Preschool Inventory- Revised (CPI; Caldwell, 1974). The CPI is an assessment and screening instrument to be used individually with children ages 3 to 6. The test was developed to give a measure of achievement in areas regarded as necessary for success in school. Included are informational, visual-motor, quantitative, language, and self-concept items. Children who fail to reach a criterion score (different for different ages) are considered "at risk." The manual reports reliabilility coefficients for the different ages as ranging from .86 to .92. The CPI was administered to children only once, when entering the school system, either at K3, K4, or KS. During the administration of the CPI, only eight children attended school per day. In this manner, the teacher was able to individually administer the CPI while a paraprofessional or classroom aide worked with the other children attending that day.

Academic Readiness. In May of their K5 year, children's achievement was assessed using the Metropolitan Readiness Test, Level II, Form P (Nurss & McGauvran, 1974). The MRT was administered to all children in groups


Table 1. Results of Hierarchical Multiple Regression Analyses

Step 1 Step 2 Step 3 Step 4 Step 5 R ~ Delta R 2

MRT-COMPOSITE SUIlTEST SCORES 1. CPI .14' 2. CPI Age .17" .03* 3. CPI Age Preschool .20* .03* 4. CPI Age Preschool Sex .20* .00 5. CPI Age Preschool Sex Age x Preschool .23* .03*

MRT-QUANTITATIVE SUBTEST SCORES 1. CPI .12" 2. CPI Age .15" .03* 3. CPI Age Preschool .18" .03* 4. CPI Age Preschool Sex .18" .00 5. CPI Age Preschool Sex Age x Preschool .20* .02*

* p < . ~ l .

of I0. Procedures for administration and scoring found in the manual were followed. The MRT is a norm-referenced test designed to assess important knowledge and skills required for first-grade reading and math. The multiple-skill battery includes: (a) auditory--beginning consonants and sound- letter correspondence; (b) visual--visual matching and finding patterns; (c) language--school language and listening; (d) quantitative--mathematical concepts and operations; and (e) a composite (sum of subtests a, b, and c) readiness score. For this investigation, only the MRT composite and quantitative scores were used in the analyses as reading/language and math have been shown to be the two best indicators of children's adjustment to the school academic routine (Alexander & Entwisle, 1988).

RES UL TS

Hierarchical regression analyses were conducted as the first step in explor- ing the effects of children's age, length of preschool experience, and sex on their academic readiness at the end of kindergarten. Results of separate hierarchical regression analyses using end-of-kindergarten MRT-Composite and MRT-Quantitative subtest scores as outcomes are summarized in Table 1. For each of these analyses, CPI scores were entered as the first independent variable in the model to control for the effects of children's risk status at the time of preschool entrance. The additional independent variables were then entered into the model in the following order: age (as a continuous variable measured in months); preschool experience (K3, K4, K5 cohort); and sex. Finally, a block of dummy variables coding the interaction between children's age and preschool experience was entered as the last step in each of the regression analyses. This final step was included to examine the possible


presence of an interaction between children's age and length of preschool experience in predicting their academic readiness at the end of kindergarten.

The regression analysis using MRT-Composite subtest scores as the outcome yielded an R 2 of .23, F(7, 4513) = 197.75,p< .001. Although the AR2's were relatively small in magnitude, the analysis nevertheless revealed that CPI scores, age, length of preschool experience, and the interaction between age and length of preschool experience each made a significant independent contribution to the MRT-Composite subtest scores. By contrast, children's sex made no significant unique contribution to the explanation of their MRT-Composite subtest scores once the effects of CPI scores, age, and preschool experience were accounted for.

The regression analysis using MRT-Quantitative subtest scores as the outcome variable yielded a similar pattern of results (R2= .20, F(7, 4513)= 167.32, p < .001). Again, CPI scores, age, length of preschool experience, and the interaction between age and length of preschool experience were each found to make a small but statistically significant independent contribution to the explanation of the MRT-Quantitative subtest scores. Sex made no significant unique contribution once the effects of CPI scores, age, and preschool experience were accounted for.

To further examine the effect of children's age and length of preschool experience on their end-of-kindergarten academic readiness, we considered whether younger children, who might be targeted to be held back from kindergarten entrance on the basis of their birthdate alone (e.g., Freeman, 1990), demonstrated lower readiness scores than older children within the same preschool cohort. We also asked whether this potential age effect was influenced by the length of the children's preschool experience.

A set of 2 (Age) × 3 (Preschool cohort--K3, K4, KS) analyses of covariance were then conducted with preschool risk status (CPI scores) as the covariate and MRT-Composite and MRT-Quantitative subtest scores as the dependent variables. Sex was not included as an independent variable in these analyses, given findings from the regression analyses showing that sex failed to account significantly for any unique variance in the academic achievement outcomes once CPI scores, age, and length of preschool experience were considered.

Results of the ANCOVA using MRT-Composite subtest scores as the dependent variable revealed significant main effects for both age, F(1, 4513) = 288.86, p<.001, and length of preschool experience, F(2, 4513)=86.39, p < .001, along with a significant age x preschool experience interaction, F(2, 4513) = 31.86, p < .001. The main effects for age reflected higher mean MRT-Composite subtest scores for older (M= 56.53) versus younger children (M= 53.46). Follow-up analyses of the main effect for preschool cohort using Dunn's procedure (p < .05) showed no significant difference between the MRT-Composite subtest scores of the K3 (M = 58.47) and K4 (M = 56.85)


Table 2. Mean Academic Achievement Scores as a Function of Age and Preschool Experience

Preschool Younger Group Older Group Experience M n M n

MRT-Composite Subtest io 58.3 (40) 58.5 (64) K4 54.7 (611) 58.9 (626) K5 52.8 (1704) 55.4 (1475)

MRT-Quantitative Subtest K3 16.9 (40) 18.1 (64) K4 16.1 (611 ) 17.8 (626) K5 15.3 (1704) 16.4 (1475)

cohorts, each being significantly higher than those of the K5 cohort (M= 54.01).

The MRT-Composite subtest score means associated with the significant Age x Preschool experience interaction are displayed in Table 2. Follow-up comparisons using Dunn's procedure (p< .05) indicated that the effect of age on the children's MRT-Composite subtest scores differed as a function of the length of their preschool experience. Within the K4 and K5 cohorts, older children obtained significantly higher mean MRT-Composite subtest scores than did younger children. No significant differences were found between the mean MRT-Composite subtest scores of younger versus older children within the 3 cohort. The effect of preschool experience on children's MRT-Composite subtest scores did not, by contrast, differ as a function of the children's age. As was consistent with the cohort main effect, comparisons within both the younger and older age groups revealed the scores of the K3 and K4 cohorts to each be significantly higher than those of the K5 cohort, with no significant differences found between the scores of the K3 and K4 cohorts (Dunn's procedure, p < .05).

Similar results were found in the second 2 (Age)x 3 (Preschool cohort) analysis of covariance with preschool risk status (CPI scores) as the covariate and MRT-Quantitative subtest scores as the dependent variable. The main effects for age, F(1, 4513)=268.1, p<.001, and preschool experience, F(2, 4513) = 72.10, p < .001, were both significant, as was the Age x Pre- school experience interaction, F(2, 4513) = 29.04, p < .001. The main effect for age was accounted for by a higher mean MRT-Quantitative subtest score for older (M= 16.9) versus younger children (M= 15.56). Follow-up analysis of the preschool experience main effect using Dunn's procedure (p< .05) revealed no significant differences between the MRT-Quantitative subtest scores of the K3 (M= 17.64) and K4 (M= 17.01) cohorts, but both were significantly higher than the mean score of the K5 cohort (M= 15.81).


Table 2 presents the mean MRT-Quantitative subtest scores associated with the significant Age x Experience interaction. Follow-up analyses using Dunn's procedure (p< .05) revealed that, as with the MRT-Composite subtest scores, the effect of age on children's MRT-Quantitative subtest scores differed as a function of the length of the children's preschool experience. Within the K4 and K5 cohorts, older children obtained significantly higher mean MRT-Quantitative subtest scores than did younger children. Significant differences were not found, however, between the mean MRT-Quantitative scores of younger versus older children within the K3 cohort.

The effect of preschool experience on children's MRT-Quantitative subtest scores did not differ as a function of the children's age group. Follow- ing the pattern of the cohort main effect, comparisons within both the younger and older age groups revealed the scores of the K3 and K4 cohorts to each be significantly higher than those of the K5 cohort, with no significant differences found between the sores of the K3 and K4 cohorts (Dunn's procedure, p < 0.5.)

DISCUSSION

There were two major purposes for conducting this investigation. The first was to determine which factors, among age of entry, prior preschool experience, and sex, contributed significantly to children's academic readiness by the end of kindergarten. The second purpose of the study was to examine what specific differences in end-of-kindergarten academic readiness existed among groups of children categorized according to those factors found to make significant contributions. An important aspect of the study was that analyses of these effects were conducted controlling for children's entry cognitive or risk status, and the findings are thus more generalizable to the broad population of young children.

Controlling for risk, age of entry, and prior preschool experience, as well as the age by preschool experience interaction, made significant contributions to the prediction of academic readiness at the end of kindergarten; sex did not contribute significantly. Earlier studies showing that sex is a significant factor affecting academic readiness (GuUo, 1991; Gullo & Clements, 1984) did not control for risk, which may help explain these disparate findings. While boys, in general, may begin schooling "at risk" as compared to girls due to differences in maturation, socialization, and prior experiences, these differences often diminish or reverse themselves in later years (Maccoby & Jacklin, 1974). Thus, controlling for risk using an instrument that measures knowledge and skills derived from prior maturation, socialization, and experience may explain the present finding that sex did not account for a significant amount of the variance in children's end-of-kindergarten academic readiness. Significant main effects were found for age of entry


and length of preschool experience. In addition, an Age x Preschool experience interaction was found.

For the K3 cohort, there were no differences between the older and the younger children by the end of kindergarten. This finding indicates that for children who will enter school somewhat young, an extra two years of prekindergarten may negate the age effect sometimes found. The children in the "young" group were below 5 years, 6 months, when they began kindergarten. According to Uphoff and Gilmore (1986), these children are "a t risk" academically and should wait an additional year before entering kindergarten. The findings of the present investigation indicate that this is not the case if these children have preschool experiences for at least two years prior to beginning kindergarten. Other studies indicate that many of the differences that are found in academic achievement between the youngest and the oldest children at the end of kindergarten usually diminish in later years (Shepard & Smith, 1988). While this may be true here as well, the nonsignif- icant difference between the younger and older children in the K3 cohort at the end of kindergarten would not have been expected based upon current research and opinion.

A second finding revealed in the interaction is that, within age group, children who were in the K3 or K4 cohort scored significantly higher on academic achievement than those who were in the K5 cohort. This finding indicates that prior preschool experience does make a difference. However, it does not appear to matter whether a child has one or two years of preschool before kindergarten. This finding is noteworthy in that it is one of the first findings indicating that preschool is effective for the general population of non-at-risk children. One of the limitations of the earlier preschool research is that it has looked at effectiveness within at-risk populations of children (Goffin, 1989). The difference found here may be due to what is being measured as an indication of academic readiness. The Metropolitan Readiness Test measures the specific types of knowledge and skills that Alexander and Entwisle (1988) indicate are good predictors of later academic success rather than any general cognitive-developmental advances that may also be occur- ring. Children participating in preschool programs presumably gain an accumulating foundation of knowledge and skills. This explanation is sup- ported by a trend in the present data which indicated that readiness scores were progressively higher among the K3 to K4 to K5 cohorts, even though the scores of the K3 cohort were not significantly higher than those of the K4 cohort.

Although this represents one of the first studies looking at preschool effects on readiness at the end of kindergarten in the general population, a number of limitations may be noted. First, although the K3 and K4 preschool groups were selected by lottery, the groups were somewhat self-selected, in that they were comprised of those families who chose to have their children


participate in the public school preschool program. However, by school district mandate, at least 50O7o of the children must come from the neighbor- hood, and citywide SES, racial, and ethnic balances must be maintained.

Although none of the children attended other preschool programs while attending the public school preschool program, it is not known whether they attended such programs prior to their participation in the public school, K3, K4, and K5 programs. This poses a second limitation of the study. While this is a limitation, the large number of children who participated in the study coupled with the statistical controls exercised should eliminate some of the confounding effects of this. A third limitation is the narrow manner in which readiness was defined and measured. Future research should broaden the set of variables measured and include family and teacher behavior measures as well. In addition, longitudinal research should be conducted to determine whether the differences described here are maintained.

This latter limitation may be the most significant limitation of all, however. Just because we can ameliorate the early effects of being the youngest child in class or boost early academic readiness through preschool education does not necessarily mean that we should do so (Katz, 1988). Future research must examine such questions as whether the types of preschool benefits identified in this study are maintained over time, or whether such benefits for children's academic readiness are achieved at the expense of other aspects of children's development and well-being. In addition, investigations of the influences of early education must be expanded to include not only assessments of the outcomes for children, but assessments of the influences that early education has on children's families and teachers, as well. Still, in total, the present study does provide findings that support the value of preschool education, particularly for children who may be at risk for academic difficulties because of biasing factors such as age. Just as important, the study confirms the complexity of the early childhood education process, highlighting the need to avoid making specific decisions about early education practice and policy in isolation from the consideration of each child's broader developmental context.

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age of entry, preschool experience, and sex as antecedents of academic readiness in kindergarten

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