This study aims to determine the antibacterial activity of isolates of microalgae Chlorella sp. against Escherichia coli, Pseudomonas aeruginosa and Xanthomonas campestris bacteria as well as produce a booklet design for class X high school protists. This research was conducted at the Laboratory of Biology Education FKIP UNRI in August-December 2020. This research was carried out in 2 stages, n…