Meh, It's okay. This game really isn't anything special. You have "x" item jumping over "x" thing. This mechanic has been done SO many times and better at that. But that's not to say this game is totally bad, there are some things that make it border-line okay.
POSITIVES:
+ High score displays everyone that's played. Nice touch on that
+ The cloud that passes every now and then is some sort of distraction, but add some more to it
+ Simplistic enough for all age groups
+ Has some addictive charm to it; you have the feeling that you want to beat your high score
NEGATIVES:
- Mediocre graphics
- No pattern to the jump rope, all you have to do is jump when it's at the highest point.
- The jumping sound effect begins to drive you crazy
- No music, add some music. Perhaps a song that starts off slow and then picks up as you progress further and further?
- Add some variation with the jump rope, start off slow and then pick up the pace little by little.
- Make the jump rope animate more smoothly, what are we playing this on? A Game and Watch?
Overall, it needs work; lot's of it! You can take this constructive criticism with grain of salt or try some things I suggest. The game has an okay base but it needs more "fuel." You can keep it the way it is or you can improve it. :)