Math is sometimes "scary" to students, so your daughter isn't alone. Based on your comments, your daughter appears to "know" the information. Try to help your daughter build a stronger self-esteem. Encourage her to do her best and then tell her not to worry. She can't do more than her best.

Tell your daughter it's common to get "stuck" on a problem; everyone does it from time to time. Encourage her to skip the one she is having trouble with by putting a dot next to its number to help her remember to return to this "skipped" problem. Remind her that unless she has read the problem wrong, usually her first impression is the correct answer.

I've included an article that talks about the fear of math in 6th graders. I thought you might find it interesting too. I've included an older article that seemed to explain things a bit better.

Hope these give you a place to get started with your daughter.