1 + 1 = ?

Morgan had a math assignment where she had to take the numbers 1-9, draw pictures representing each one (one cat, two clouds), add one more to the picture and then write out the math sentence. For some reason, she just wasn't getting that the answer is always going to be the next numerical number. For example, to figure out 7+1 she would start counting from one. I kept explaining that it would be 8 because 8 comes next. Then she got to 9. While drawing 9 figures she lost count of how many she had already drawn. I told her to count what she had. She counted four. I asked her how many she still had to draw and without skipping a beat she replied five.

So... was she just bored with the simplier equation and therefore not concentrating or what?