Put a flat of a hundred squares next to a single cube and ask a seven-year-old which one is worth more. The answer is obvious to the eye, and that is exactly the point. This 2nd grade base ten blocks addition worksheet lets the drawing carry the meaning of each digit. There are only two problems, 215 + 324 and 463 + 120, but each number is drawn in full: big square flats for hundreds, tall rods for tens, small cubes for ones. A girl with a hula hoop keeps an eye on the second problem. Your child counts the pieces place by place, then writes the sum on the line. A second page gives the answer key.