getting a better straightener is probably what you need.
save your allowance or whatever money you can get
put it in a glass piggy bank that has no holes in the bottom so
that way you wont' be tempted to get the money.
and sooner or later you'll have enough money to get a good straightener
the good ones can be $80 - $150 sometimes
i recomend a chi
and also another tip,
when your done doing your hair
don't touch it and don't let anyone touch your hair
because hands can be dirty and then idk its just nasty
to have dirt in your hair and also touching your hair will make it
frizzzzz up.
good luck :]]
(by the way: i did the piggy bank thing and had 120 dollars at the end of 3 and a half months! all from allowance and i got a chi! you should try it)