I don't know if this will help but I had trouble dealing with the traditional method of the flashcards and am a very visual person. So my parents made a chart on poster board like a large graph, with lines going horizontally and vertically then filling in 1-12 across the top and 1-12 down the side. Then with their guidance, they had me fill in the rows and columns with the answers. Then they had me highlight with markers using different colors for the rows or columns (whichever one they prefer, such as alternating a colored row or column with a non-colored one), and then specifically coloring the angled boxes where the numbers timed themselves (answers for 1X1, 2x2, 3x3, etc) with its own same color (highlighted in yellow say) as a way to see how this happens and to break up all the numbers on the board.

Then for practicing we would go across and cover each box up as we would go, with me having to repeat it, look at uncovered, cover it again and repeat the answer back; then move on to the next. Trying to make a rhyme out of it as well. Then it got to where they taped construction paper to cover up whole rows, using it more as a test once had them down better and I could test myself. We worked on 1-2 rows at a time every day, then once could do them pretty well without looking, mostly, then moved on to the next 1-2 rows. Had them down in no time.

This helped give a frame of reference for the numbers in relations to one another unlike the dealing with the flash cards. Used these later once had them down better. This method helped my niece and my neighbor too. Perhaps it might help. Good luck!!!!!!