This works much better
Having had a professor that pointed things out with a yardstick in the classroom, it should be noted that it's a great tool to reorient student attention to the front of class, especially when said professor was a pretty strong cricket batsman....
All my professors did this, because i'm old.
and they did a good job hiding the filmstrip machine.
I haaaaate laser pointers. Our department has a long bamboo pokin' stick that we all use.