Photoshop
"How to Photoshop yourself into the class photo"
Open your two or three photos (background, you, your book) in Photoshop.
Select all (command + A) of the photo of you and copy (command + C).
Paste onto the background photo. It should appear as a new layer.
Rename this layer to your name.
Remove the background behind you by using the "Magic Wand" and "Polygonal Lasso Tool" (my recommendations). Do this incrementally until you've removed the background.
To resize yourself, transform (command + T) on your layer and use the corners to resize and position yourself in a good place in the background.
Our result
