Teach your students accountability and never lose a single pencil again!
I teach in a sixth grade math classroom and for summer school I've introduced this awesome system. Each of the 10 classroom pencils have a flag on the end made out of washi tape that is clearly labeled with a number.
To borrow a pencil, students sign it out using this sheet and return it as they leave the room. (The sheet as blank space at the top so it can be held by a clipboard.)
During the regular school year I will introduce the "pencil monitor" job. This student(s) will check our pencils at the end of class to ensure that they have all been returned. This will also be the only student who is permitted to use my electric pencil sharpener.
So far, I haven't lost any pencils! And we are considering incorporating this system in all of our sixth grade classrooms.