This document introduces an e-learning network in mathematics across universities in Saxony, Germany. The network shares electronic assessments created using ONYX and MAXIMA. Over 50 authors have created more than 1000 questions across various topics in mathematics. The assessments provide interactive practice and feedback for students and inform instructors. OPAL is the central learning platform used by 80,000 members across 11 universities. ONYX allows for different question types and MAXIMA can analyze student responses with random parameters and expressions as answers. The speaker's university courses use 4 online tests throughout a semester to provide practice for approximately 200 students.