#1:Go to lavalava island and fight the fuzzy,make sure you have the zaptap badge(if not,then go to the badge trader who trades badges for star peices) at merlee's house,then,the fuzzies can't hurt you and they take 1 damage!(just choose do nothing every round,and they will keep multiplying,for ultimate star points!) but if you are to high level to get experience from them,then try these other ones!
#2:At the flower fields,go down the bottom right path,then go until you see a flower creature that is shining,now fight him(he will try and run away) he is tough,does 20 damage and takes about 15 damage to kill,but you get 40 star points for killing him!(once you kill him,go 2 screens back then go back,if he isnt there again,try again until he is back)
#3:Once you beat lavalava island's boss and get the spirit,go to pleasent path,and you will find a HUGE koopa,fight him,(note,use watt or goombario,better if goombario is ultra ranked) now,use the star power,"Chill Out" and then try and defeat him,it gets easy as you fight him,cause u'll find out some new ways to beat him,like I did...he gives you 30 or 40 star points!