I asked, still trying to keep everything straight in my head.

That added up to a lot of things to keep in my head during lessons.

"How are you ever going to keep it all in your head?"

I never knew how she could keep so many things in her head.

I used to be able to keep everything in my head.

This is information you don't want to keep in your head.

Now, if he could just keep a thought in his head long enough to do something!

You have to keep in your head: what's the worst that can happen?

And you told me you've kept a running total in your head all the year.

I kept the goal strongly in my head for years.