This was a worksheet I made as my 1st lesson on graphs of quadratic functions.
I started out the lesson by showing students the basic form of y=x^2 equations and what they look like on the graph by doing the 1st problem. After having them graph it, there is no trouble finding someone who can explain/guess how to make the 2nd graph (y=-x^2)
For the rest of the worksheet I make sure they know how to use the table function on the calculator and then leave them to work in pairs or small groups. This worked out well because it let them discover for themselves the many ways they an change the shape of the graphs as well as building familiarity with the calculator.
This powerpoint file is meant to be printed and copied for the students to use. The last 2 slides are the answer key.