I found this poem in the collection Philosophia Patrum edited by Julius Wegeler.
Vivamus, Discamus
Vivamus puri quasi simus cras morituri;
Discamus veluti simus de tempore tuti.
The vocabulary is keyed to the DCC Latin Vocabulary list. There are two words in this poem that are not on the DCC list:
crās: tomorrow
pūrus, -a, -um: pure, clean
dē: down from, about, concerning (+ abl.)
discō -ere didicī: learn
morior morī mortuus sum: die
quasi: as if
sum, esse, fuī: be, exist
tempus -oris n.: time
tutus -a -um: safe, protected
velut: even as, just as
vīvō vīvere vīxī victum: live