A teacher purportedly send this to her elementary graders. She only gave the 
first half of many well known sayings, and ask the students to complete the 
other half. The result is a refreshing way to look at many everyday beliefs.

Better to be safe than ... punch a 5th grader.
Strike while the ... bug is close.
Never under estimate the power of ... termites.
You can lead a horse to water but ... how?
Don't bite the hand that ... looks dirty.
No news is ... impossible.
A miss is as good as a ... mister.
You can't teach an old dog new ... math.
If you lie down with dogs, you'll ... stink in the morning.
Love all, trust ... me.
An idle mind is ... the best way to relax.
Where there's smoke there's ... pollution.
Happy the bride who ... gets all the presents.
A penny saved is ... not much.
Two's company, three's ... the Musketeers.
Don't put off till tomorrow what ... you put on to go to bed.
Laugh and the whole world laughs with you, cry and...you have to blow your nose.
Children should be seen and not ... spanked or grounded.
If at first you don't succeed ... get new batteries.
You get out of something only what you ... see in the picture on the box.
When the blind leadeth the blind ... get out of the way.
Better late than ... pregnant.