A National Science Foundation-funded study (N = 85, p < .01) at Manor Independent School District found significant gains in science concept acquisition using Speak Agent with a dosage of just 30 minutes per week. More than 80% of the students were classified as English learners (ELs).
Findings

Students in the treatment group who used Speak Agent improved their performance on an independent assessment of science concept knowledge by an average of 10.3% vs. 2.8% improvement for the control over the first 12-week period. That represents a tripling of the average learning gains. In a second 12-week period, performance improved by 15.3%. The results were so strong that the researchers moved the control group to the treatment in the second phase.
Read more about it in this case study from District Administration.
Study Methodology
Manor ISD teachers administered a pre-test and post-test each semester designed by independent evaluator Rockman et al. The tests consisted of 20 varied questions covering 34 science concepts. All definitions and images were carefully selected to avoid any overlap with those used in the Speak Agent program. Rockman et al graded all of the tests. Students in the experimental group used Speak Agent for an average of approximately 6 hours over a 12-week period using tablets, laptops, and desktops (varying by classroom and availability). Students in the control group spent the same amount of time receiving standard science instruction without Speak Agent.