It's just okay.
1. There's not a lot of variety in the game play. There are two games; catch the egg that matches the word, and spell the word.
2. It leaves the word you're trying to catch UP on the screen; it'd be better if the first five catches the word was there, but it disapears after a certain amount of time.
3. It takes TOO LONG to move on and get a reward! When you find the word ten times, it shouldn't KEEP GOING, that doesn't keep kids' attention...they get bored and drift off. Mine kept asking how many more he had to do. There should be a change of skill set at a successful spotting of 10; do another skill, then on. Looking for the same word 20 times? Boring. The rewards don't come soon enough.
4. A reward of more turns (spotty eggs, puzzle pieces) isn't a very good reward. Those should be used to unlock a new activity involving the same words. You can even do the same concept, different application: make the words hidden in a story page; you could even keep your same theme: find 10 instances of the word 'came' in the farm, in the barn, in the pasture, in the kitchen, etc. More variety, reinforcing the word but keeping it interesting.
This isn't BAD for $3.00, but there's not enough variety of play to make it through all 250 words, and that's a shame.