2 Davico (1590) found that poor teachers and iniadequate support to poor children are to blame for the high rates of repetition and drop out in Brazil. It is often the case that the poorest teachers are to be found in the first grade. There is also evidence of discrimination against students from disadvantaged backgrounds, and a belief among teachers that poor students cannot learn. The teaching method reinforces such attitudes, leading to high rates of repetition and drop out for those from disadvantaged backgrounds. Schiefelbein also finds that repetition is especially severe among the most deprived; that is, those whose parents have the lowest levels of education and income are more likely to repeat a grade (Schiefelbein 1992: 7). Recent research for Uruguay has found that repetition decreases significantly as the level of the parents' education income increases (Schiefelbein 1992: 6).

Repetition rates are also high among those living in rural, isolated areas, and among indigenous peoples and non-whites. It has been found that the repetition rate is twice the national average in Malleco province in Chile, which has the highest proportion of indigenous people in the country (Schiefelbein 1992). Significant differences by gender have not been detected, and although girls in general do- better than boys, gender differences have been diminishing over time (Schiefelbein 1992: 8). Schiefelbein (1992, 1989, 1975) adds some further explanatory factors, such as children with learning disabilities, "age heterogeneity' in the classroom (see below), language and, in some cases, the lack of bilingual education.

Psacharopoulos and Yang (1991), in their study of educational attainment in Venezuela, also examined the problem of repetition. Using a 1987 sample of school children aged 10 to 18 years, they found that grade repetition was associated with urban areas (negative) and with being male (positive). They also established that family background (father's education) has a significant effect on lowering the repetition rate.

Regarding the determinants of grade repetition, Schwille et al. (1991) presented a detailed causal model to explain grade repetition. Three main categories were put forward, including: student characteristics, such as gender, ethnicity, family influences, place of residence, age, prior repetition experience, aptitudes, and perceived opportunities for work/employment; national policies regarding language, repetition, secondary school entrance, other access and selection policies, and the quality of instruction; and school characteristics, such as school management practices, coverage of syllabus, quality of instruction, compliance with national policies, and the capacity of the school relative to the number of non-repeaters. All this is hypothesized to cause repetition, which in turn affects student leaming, student motivation, student self-esteem, the examination success rate, the enrolment rate, the dropout rate, and the mean time required to produce graduates.

The demand for child labor, whether paid or unpaid, affects schooling, often causing grade repetition. This relationship was examined by Bowman and Goldblatt (1984), who found that the demand for the productive contributions of children to the household economy are closely associated with "overage" and the proportions of youth who do not complete even four years of primary schooling (Bowman and Goldblatt 1984).