Disagree with soil, learn, and cheap. You should accept "dirt" or "ground" or "earth" for soil, "study" for learn, and "peace" for cheap. It's unfair to relegate one definition to a single kanji when they can hold multiple meanings.
Nice useful quiz; but i agree with others who complain about 'feeling' 'cheap' 'learn' and 'soil' - also, i'd learned above/below rather than up/down...but would love to see more!
"Feeling" for 気 is not even accurate (this would be 情), while "energy," "spirit," or "qi" would all be more appropriate, but weren't accepted. 地 should accept "land," 高 "high," 安 "peace" (this is the main meaning of this kanji), 力 "strength," and the numbers should allow the spelled out words in English.