Here is a list of great printable kanji practice sheets! On all of these sites, the kanji are divided by grade level. Master the First Grade (一年生) kanji, then go to the next level. Please leave a comment if you know of any other great websites or resources for learning kanji.
1. Happy Lilac
Happy Lilac also has other great printables for elementary-aged children HERE.
(This website might be by the same people who made the Happy Lilac website… they look very similar)
This website doesn’t have printables, but has great interactive games for reviewing kanji