The children's aunt decided to take their education in her hands.

[Rachel Adams]

What verb or idiom can I use to talk about someone who decides to become responsible for her nieces education? Can I use "take something in her hands?"

The children's aunt decided to take their education in her hands.

 

[emsr2d2]

What verb or idiom can I use to talk about someone who decides to become responsible for her nieces' education? Can I use "take something in her hands?"

The children's aunt decided to take their education in her hands.

You could end with "into her own hands". That's a set phrase.

 

[teechar]

The children's aunt decided to take responsibility for their education. in her hands

or

The children's aunt decided to take care of their education. in her hands.

or

The children's aunt decided to take their education into her hands.

or

The children's aunt decided to take look after their education. in her hands.

Those are all possible, depending on what you mean. What exactly did the children's aunt decide to do regarding their education?

 

[probus]

"Into her own hands"is much more natural than "in her hands". In fact I'd go so far as to say that "in" is wrong there.