The use of technology in schools, and especially computers, is increasingly popular. Yet according to Professors Joshua Angrist and Victor Lavy, writing in the latest issue of the Economic Journal, there is no evidence that computer-aided instruction (CAI) is an effective way to teach. Their research detects no improvement in pupil performance from the massive influx of computers into schools. Indeed, computerisation may even have lowered student achievement in mathematics.
The question of whether educational technology is effective is of much more than academic interest since the infrastructure for CAI is expensive and may take resources from other educational uses. The most important shortcoming in the case for further investment in CAI infrastructure is the fact that the evidence for effectiveness is both limited and mixed. Although CAI has been around for&##160;decades, there are few empirical studies that meet a rigorous methodological standard.
Angrist and Lavy provide new evidence on the educational consequences of CAI. Their study exploits an episode in Israel that facilitates controlled comparisons. In 1994, the Israeli state lottery, which uses lottery profits to sponsor various social programmes, funded a large-scale computerisation effort in many elementary and middle schools – the Tomorrow-98 programme.
By June 1996, about 10% of the country''s elementary school pupils and about 45% of the country''s middle schools pupils had received new computers as a consequence. This programme provides a valuable ''natural experiment'' that can be used to study the impact of a sudden shift in the extent of educational technology by comparing otherwise similar schools that did and did not receive new computers.
The results show that the influx of thousands of new computers in 1994-5 led to a substantial increase in the use of CAI in elementary schools, with smaller effects on usage in middle schools. In particular, the likelihood that fourth-grade teachers used the computers to teach mathematics went up by about 20 percentage points as a consequence of the new machines.
But there is no evidence that increased educational use of computers actually raised pupil test scores. In fact, the best estimates show that the mathematics scores of pupils in schools that received new computers actually went down. In eighth-grade maths and in language classes, there was no effect either way, perhaps because the new technology changed instruction methods by less than in fourth-grade maths.
A possible explanation for these findings is that CAI is no better and may even be less effective than other teaching methods. Alternately, CAI may have consumed school resources or displaced educational activities which, had they been maintained, would have prevented a decline in achievement. The research finds no evidence of a significant change in the extent to which other sorts of educational resources were available, nor in instructional methods or teacher training in Tomorrow-98 schools, suggesting that there was no displacement. On the other hand, while Tomorrow-98 included a training component, CAI strategies implemented with a large increase in teacher training may prove to be more effective, though also more costly.
Another possible explanation for the findings is that the transition to CAI is disruptive, and
any benefits of CAI take time develop. The schools in the sample had Tomorrow-98
computers for an average of one full school year. This may not be long enough for any
benefits to appear. It should be emphasised, however, that enough time had passed by the
test date for the new computers to have had a large and statistically significant impact on
instructional methods for fourth-graders. In addition, even if the decline in scores is shortterm,
this is an extra hurdle to overcome if the transition to CAI is ultimately to be justified
by academic achievement.
Finally, an important feature of Israel''s computerisation programme, and an element that is
by no means unique to Israel, is the large cost of a broad move to CAI. Programme
schools received an average of about 40 computers, for a cost of $120,000 per school. In
Israel, this amount would pay the wages of up to four teachers. Assuming a depreciation
rate of 25% on hardware and software and ignoring any training costs, the flow cost of the
computers is about one teacher per year per school.
Recent years have seen similarly ambitious computerisation efforts in schools elsewhere
in the world. In the United States, for example, education technology is thought to have cost
$5.2 billion in 1998, and the proportion of elementary school classrooms with internet
access jumped from 30% in 1994 to 75% in 1997. The question of future impact remains
open, but this kind of expenditure on education technology does not appear to be justified
by pupil performance results to date.
''New Evidence on Classroom Computers and Pupil Learning '' by
Joshua D. Angrist and Victor Lavy is published in the October 2002 issue of the Economic
professor of economics at University of Warwick and the Hebrew University of Jerusalem