smarten up
undumb
greenly
nerdify
cop on
fledgling
act one's age
derp
wisen
stupefying
sheep-headed
outfake
ungrown
outdumb
not as green as one is cabbage-looking
naivety
greenhornism
ripen
grow into
unfoolish
melt
laxen
mellow
mellow out
buffoon
sapient
naif
lighten
get over oneself
dote
deaden
dephilosophize
cut one's eyeteeth
tepefy
unstupid
nonstupid
maddle
sap
nonintellectual
mature
unbitch
eyewash
stupidify
naivistic
weasel
sapheaded
naïve realist
suffer fools gladly
coolen
outstupid
arse
unreasonably
unintellectual
duncify
unamateurish
rareripe
soften up
unperk
dull
jejunely
pall
infantile
indehiscent
unbefogged
immaturely
tire
alliteratively
dewy-eyed
childish
resolve
maturely
idiotize
cheeser
unidiotic
intellectual
gosling
naifly
ultracrepidate
submoron
dim
smartish
grow out of
gay-ass
wise
four oh four
drool bucket
piffle
wise off
sophisticate
unwise
child
tardlet
baby
vary
dumbify
take leave of one's senses
insipient