If your students have their own folders in the shared network drive I would have them create All About Me powerpoints. Each slide can be their favorite this, that, or the other...
Definitely go over rules of the tech lab first and foremost though.
If you have a color printer, they could all go in paint and draw a picture to represent their summer vacation. They could save the picture, import it into word and type a couple of sentences about it. Then print it out. (vary level of difficulty by grade level)
Young students could all open a picture you've found on line from a coloring book of summer vacation. They can use the paint bucket to fill in and color the picture then they could use the text tool to type their name and maybe a sentence or two depending on age level/ability and print that out.
Those are just the first things that pop into my mind. Sure wish I had your job!!
