STYX 1.0 is a corpus of Czech sentences selected from the Prague Dependency treebank. The criterion for including sentences into STYX was their suitability for practicing Czech morphology and syntax in elementary schools. The sentences contain both the PDT annotations and the school sentence analyses. The school sentence analyses were created by transforming the PDT annotations using handcrafted rules. Altogether the STYX 1.0 corpus contains 11 655 sentences. Originally, the STYX 1.0 corpus was an inseparable part of the Styx system (http://hdl.handle.net/11858/00-097C-0000-0001-48FB-F)