During the homework mission you start out at the school. go right from where you start and when you get to the dead end(wall) go up. at the end of the alley, there should be a yellow orb. Touch it, and a circle of yellow orbs should appear gat them. Now press start, save your stats and repeat. The Yellow Orb is back! Repeat until he reaches the level you want him to be. (I got him to level 25 and beat sakamoyuto(sp?) in one punch AND I got all all Kawabaras attacks but spirit sword.) Enjoy your Kawabara!
A great tip for leveling up: In boss battles and levels full of lots of enemies, use them to get level ups. Go through the level/battle, and right before the end, or after you take the circle of exp. orbs, if you've collected lots of exp., press start and choose "save Stats". You will restart the level with all previous stats, save now all characters have full HP! It is also an effective tip if you got lots of Exp. since the start of the level and are about to die. The best levels I've found are the Triad, Vs. Kuwabara, Vs. Byakko, the maze in the castle, Vs. Genbu, Vs. Sakamoto & the thugs, and best of all, the cultivated humans/stairs/Vs. Suzaku. *Pant, *Pant...
Beat all the levels even the mini bosses after you fight toguru then it will say you unlocked extras.Ps you could only play as genkai.Genkai has good stats at level 15 but you can not level up.
Early in the game, you'll find a level where you must collect homework papers in the area. You must have at least 10 to win the level, but something special happens if you get all of them. I'f you get all 20, the game will say your health has permenantely increased. I can't tell if it's true or not, but that's what it says.
Play with Hiei and use his teleport ability on the sides of buildings and he will teleport to the roof above them.