Schematic diagrams are data modelling tools used for databases, they defined the entities, attributes and the relationships between entities...
An easy way to understand it i guess, is through visualising it...
Take one to many relationship for example:
1. teacher (one) to courses (many) means that one teacher can teach many courses but at the same time each courses is only taught by one teacher...
2. Student (many) to courses (many) means that a student cound be doing more that one courses and at the same time each courses can have many students...
and so on so for one-to-one... many-to-one...etc
I've tried using Microsoft Access for my database assignment and finds the same problem with defining relationship... it seems that Access automatically set all relationships to one-to-many... i dun know how to change it yet but check the help menu~~
hope this helps
best luck for ur IPT trials