Africa has a high student-to-teacher ratio which limits students' access to teachers for learning support such as educational question answering. In this work, we extended Kwame, a bilingual AI teaching assistant for coding education, adapted it for science education, and deployed it as a web app. Kwame for Science provides passages from well-curated knowledge sources and related past national exam questions as answers to questions from students based on the Integrated Science subject of the West African Senior Secondary Certificate Examination (WASSCE). Furthermore, students can view past national exam questions along with their answers and filter by year, question type, and topics that were automatically categorized by a topic detection model which we developed (91% unweighted average recall). We deployed Kwame for Science in the real world over 8 months and had 750 users across 32 countries (15 in Africa) and 1.5K questions asked. Our evaluation showed an 87.2% top 3 accuracy (n=109 questions) implying that Kwame for Science has a high chance of giving at least one useful answer among the 3 displayed. We categorized the reasons the model incorrectly answered questions to provide insights for future improvements. We also share challenges and lessons with the development, deployment, and human-computer interaction component of such a tool to enable other researchers to deploy similar tools. With a first-of-its-kind tool within the African context, Kwame for Science has the potential to enable the delivery of scalable, cost-effective, and quality remote education to millions of people across Africa.

翻译：非洲地区师生比例较高，限制了学生获取教师学习支持（如教育问答）的机会。本研究扩展了面向编程教育的双语AI助教Kwame，将其改造为适用于科学教育的工具，并作为网页应用部署。Kwame for Science系统可从精心筛选的知识源中提取文本段落，并结合西非高中证书考试（WASSCE）综合科学科目的历年真题答案，为学生提供问答服务。此外，学生可查看历年国家考试题目及其答案，并通过年份、题型以及我们自主开发的话题检测模型（未加权平均召回率91%）自动分类的主题进行筛选。经过8个月的真实环境部署，该系统覆盖32个国家（其中15个为非洲国家）的750名用户，处理了1500个问题。评估结果显示，前三准确率达87.2%（n=109个问题），表明Kwame for Science在显示的3个答案中至少提供1个有效答案的概率较高。我们系统梳理了模型错误回答的原因分类，为后续改进提供依据。同时分享了此类工具开发、部署及人机交互环节的挑战与经验，以帮助其他研究者部署类似工具。作为非洲首创的此类工具，Kwame for Science具备为非洲数百万用户提供可规模化、高性价比及优质远程教育的潜力。