"did i make it clear" = the Teacher is asking the students if they explained it clearly and did they the students understand
"let me make it clear" = the teachers saying
1. let me tell you with no uncertainty, used as a reprimand.
2. let me say it clearly, it implies the teacher will next explain clearly,
"let me get it clear" = the interlocutor (person speaking) is asking for assistance or further explain or is doubting themselves.