Answer:
When I get closer my tail grows longer, but when I go away my tail leads the way.
Double my number, I'm less than a score. Half of my number is less than four. Add one to my double when bakers are near. Days of the week are still greater, I fear.
This thing runs but cannot walk, sometimes sings but never talks. Lacks arms, has hands; lacks a head but has a face.
What instrument can make any sound and be heart, but not touched or seen?
A mighty weapon in the war against winged household pests.
I can only be played on a windy day