This article describes a new approach to teaching bioinformatics using "Arabidopsis" genetic sequences. Several open-ended and inquiry-based laboratory exercises have been designed to help students grasp key concepts and gain practical skills in bioinformatics, using "Arabidopsis" leucine-rich repeat receptor-like kinase (LRR RLK) genetic sequences. In these exercises, students are asked to explore the intimate relationship between the structure and functions of LRR RLKs and to understand the diverse signaling roles of LRR RLKs in "Arabidopsis". Students are also required to identify LRR RLK paralogs and orthologs and to analyze their evolutionary and functional relationships using bioinformatics software. Through these exercises, students are expected to gain the ability to search databases to retrieve genetic data and analyze them using a variety of bioinformatics tools. (Contains 3 tables, 4 figures and 1 footnote.)