Creating a list from a datagrid?

Question

I'm very new to Visual Basic. I have discovered that it is much easier to design the form than it is to make it work with code. I'm a college student. I'm trying to make an application that will help me keep track of my assignments.

I have three textboxes. They are assignment name, class name, and due date. I want to push the "Add Assignment" button and move all the text from the boxes into three columns in a datagrid. I've figured out how to code the datagrid to create a new row when the button is pushed, but I can not find out how to put the text into the row that is created. What sort of code would do this?