Perhaps John Donne's Holy Sonnets 10? Donne explicitly argues that sleep is better than death. He doesn't call sleep an equalizer, but he does say that death is a "slave to ... kings and desperate men", which sleep isn't:
Death, be not proud, though some have called thee
Mighty and dreadful, for thou art not so;
For those whom thou think'st thou dost overthrow
Die not, poor Death, nor yet canst thou kill me.
From rest and sleep, which but thy pictures be,
Much pleasure; then from thee much more must flow,
And soonest our best men with thee do go,
Rest of their bones, and soul's delivery.
Thou art slave to fate, chance, kings, and desperate men,
And dost with poison, war, and sickness dwell,
And poppy or charms can make us sleep as well
And better than thy stroke; why swell'st thou then?
One short sleep past, we wake eternally
And death shall be no more; Death, thou shalt die.
Admittedly this is a long shot, as I'd not expect American teenagers (even those taking AP English) to be able to tackle Donne in an exam setting.