ebullient

boisterous, bubbly, exuberant, high-spirited

active, airy, animate, animated, bouncing, brisk, energetic, frisky, gay, jaunty, jazzy, kinetic, lively, mettlesome, peppy, perky, pert, pizzazzy (or pizazzy), racy, snappy, spanking, sparky, spirited, sprightly, springy, vital, vivacious, zippy

dapper, dashing, spiffy

agog, alert, awake, open-eyed, up, wide-awake

agile, nimble, spry

bright, buoyant, cheerful, chipper, chirpy, chirrupy, effervescent, sparkly, upbeat

eager, enthusiastic, keen

frolicsome, impish, pixieish, playful

high-strung, nervous, skittish