The importance of time as a resource in Carroll’s time model
In 1963, Carroll outlined the theoretical importance of time as a resource for student learning. He
conceptualised the degree of student learning as a product of the time students spend learning divided by
the time they need to learn (Figure 1.1). The time students spend learning depends on their opportunity to
learn (time allocated for learning) and their level of perseverance (time engaged in learning). Instruction
time, or the total number of allocated classroom hours, accounts for a major part of public spending on
non-tertiary education and constitutes a key resource that offers opportunity to learn (OECD, 2013a).
The
time needed for students to learn depends on their aptitude, the quality of instruction they receive and their
ability to understand the instruction. Carroll’s model suggests that, everything else being equal, increasing
the time that students invest in learning will lead to better academic performance and, consequently, that
deciding on the amount of instruction time is a key decision for policy makers (Berliner, 1990;
Bellei, 2009; Brown & Saks, 1986; Carroll, 1963, 1989).
Figure 1.1 Theoretical importance of time for student learning: The Carroll Model
𝐷𝐷𝐷𝐷𝐷𝐷 𝑜𝑜 𝑙𝑙𝑎𝑟𝑟𝑟𝑟𝑟
= 𝑓 � (𝑇𝑇𝑇𝑇 𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎 𝑓𝑓𝑓 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙) × (𝑇𝑇𝑇𝑇 𝑒𝑒𝑒𝑒𝑒𝑒𝑒 𝑖𝑖 𝑙𝑙𝑙𝑙𝑙𝑙𝑙𝑙)
(𝑇𝑇𝑇𝑇 𝑛𝑛𝑛𝑛𝑛𝑛 𝑡𝑡 𝑙𝑙𝑙𝑙𝑙) × (𝑄𝑄𝑄𝑄𝑄𝑄𝑄 𝑜𝑜 𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖𝑖 × 𝐴𝐴𝐴𝐴𝐴𝐴𝐴 𝑡𝑡 𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢𝑢)
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Berliner (1990) argues that the Carroll model can be used to compare the more efficient use of time
and also to account for the use of scarce time resources, such as the teacher’s planning time or the time
devoted to one-on-one instruction.
Added value and limitations of the paper
This paper attempts to examine the allocation and use of student learning time as a key educational
resource. It provides an overview of the allocation of student learning time in OECD countries. Based on
an overview of research, it develops and presents a model to understand the effective use of allocated
instruction time and illustrates different phenomena of time loss and how these vary among OECD
countries.
A model to analyse the effective use of allocated instruction time
In an aim to understand how effectively allocated instruction time is used, the following concepts are
analysed:
• Allocated instruction time: the annual intended number of hours that students should spend in
formal classroom settings, learning compulsory as well as non-compulsory parts of the
curriculum as per public regulations (OECD, 2011).
• Actual lesson time: the amount of allocated instruction time remaining for actual instruction after
initial losses due to exceptional school closures and teacher and student absences or lateness.
• Engaged time: the amount of actual instruction time, once time spent on administrative and
disciplinary issues has been subtracted, during which students seem to pay attention
(Berliner, 1990).
• Actual learning time: the time during which students are focused on academic material of
relevant difficulty that allows them to experience success (Cotton, 1989).
EDU/WKP(2016)1
8
Limitations
First, this paper aims to provide an overview of different practices among OECD countries in how
they organise compulsory education and allocate instruction time. To do so, it brings together information
as reported by countries on a common international indicator framework. While this has the advantage of
providing a greater degree of comparability, it must also be borne in mind that OECD countries report this
information in a variety of ways, sometimes drawing on central specifications, sometimes on survey data
and sometimes providing estimates from different sub-national information. Also, information may relate
to minimum, recommended or even total instruction time, depending on the country.
Second, this paper aims to examine the effectiveness and efficiency of different approaches to
organising student learning time. The paper presents a summary of research, but this is subject to several
limitations:
• Lack of information on costs: Most of the quoted research focused on effectiveness, or measuring
whether different time allocations influence student achievement. Very few of the studies looked
at the costs of different uses of time. Research on student learning time has not yet developed a
comprehensive model that would allow for analysis of comparative cost-effectiveness. This
shortcoming raises a bigger question of how to measure costs borne by the society as a whole; for
example, the cost of organising supervision for children in the absence of after-school services,
that are usually borne by parents. In the face of scarcity of efficiency studies, the primary
suggestion for further study is to develop this strand of research.
• Inconsistent ways of measuring “time”: Research on student learning time is complicated due to
the inconsistent ways of measuring and defining concepts across literature, with some studies
making only generic references to “school day” or “class time” (Aronson, Zimmerman and
Carlos, 1998). Definitions of “time” vary significantly in education research and may confound
the influence of time with aspects of teaching quality (Scheerens et al., 2013).
• A dominance of correlational data: Most of the quoted research relied on correlational data with
time constructs as independent variables and test scores as dependent variables. There are
comparatively few longitudinal or experimental studies that allow inference of a cause and effect
relationship. Since most of the studies on the topic adopt a short-term perspective, they usually
measure achievement through pre-test and post-test in the form of tasks to be completed.
This
approach offers only limited insight to the long-term results, given that schooling clearly has also
non-academic benefits. Also, the paper draws heavily on results from cross-sectional
international studies to examine how effectively instruction time is used. Relationship with
performance cannot be clearly established, as no causal inferences can be drawn from crosssectional data. There is a complex relationship between instruction time and student performance,
e.g. some countries may increase instruction time as a measure to combat low performance, but
this may not be sufficient to redress other educational differences compared to other OECD
countries
.
• Lack of geographical coverage in research: The lion’s share of research quoted in this paper is
from the United States with regard to studies on the effective use of time. The paper also draws
heavily on research from France on students’ learning rhythms. It is highlighted where this
research has been validated in other countries, but caution must be taken when generalising
findings internationally