You need to rework your flash focus. If I go to another tab, all the creeps just sit still, as your motion along the path isn't incrementing. The shots from the towers, however, do continue iterating, and pile up when the focus is away. Not a bad first start, though. Let's see the rest of those ideas you've got!
I'd recommend making Keypad - and + also move your tower focus around, and maybe / and * be for repairs and upgrade on the current row. That would put all of the games controls in one hand. (Otherwise, this is just too frustrating a control schema to play.) I like the concept a lot, though. I don't see nearly enough educational games these days, so kudos to you for making one.
This was a surprisingly fun take on an old classic. I would recommend, though, much like the original, an option for different size boards, for those who want different game length options.
part 2:
All in all, a decent start. If you're going to keep working on this, I'd recommend a couple days working on integrating textures, as opposed to straight bitmaps, as it will help the visuals drastically. Even some simple things like rounding off the corners can make it look much smoother. Also, if you're going to move forward with this, I would remove the "points", and roll in a earned cash function. Once you've got it working well, balance, specifically things like interest, and whether towers are too strong or weak, can come later.
Okay, time for constructive feedback: I do like the mouse-over for the towers, but the contrast makes it difficult to read. Some simple textures or color differentials could fix that. I also like the pause when you click outside the flash base. That's good UI design. The cost should be listed for the towers, because you've provided coins as a numerical value. For example, since the life of the creeps is not displayed as a number, keeping the damage listing as "weak" or "strong" is fine (I think it adds character, actually). However, any time you're providing a heads up on any numerical value, there should be a corresponding numerical feedback to the player. In the same vein, it wouldn't make sense to say "damage, 10 pts" if there was no numerical gauge on the creeps. Keep your numbers together and your subjective descriptors grouped together.
As someone who's worked for an online gaming site, I can say that a pop-up mid-game, even between levels, is probably the worst user experience choice I've ever seen (and I've seen it many times). You should never detract from the experience at hand with an unanticipated redirection. It doesn't matter how good or bad the rest the of the game is: If the user is given the bait-and-switch feeling and doesn't want to stick around and play, the experience of the game will always be bad for the player.
Absolutely Brilliant. This is what I love to see here, gaming raised to an art form. I also love that, whether people notice it or not, there is a meta-game between you as the creator and us as the players, embedded in the overall theme.
The natural response of someone to fling an opponent is to fling it as far as possible. Unfortunately, once you go outside the range of the flash border, the mouse click disengages, and the enemy drops before the pointer can catch them up to your mouse coordinates. If you added a momentum function to your mouse-off routine, this would be a lot more playable.
Also, there's a scale issue when you can't even get a tower in this tower defense game until at least level 4. You should consider adding a simpler very cheap tower or maybe an electrified fence, so the player isn't just watching their fence die while they fail to throw the enemy.
It seems once you manually switch to the freeze cannon, you can't switch back. Since the game autosaves, that makes it impossible to ever do anything again.
Things this needs: Game field needs clearer definition. A life meter to show how far along you are. A timer showing time till net wave. De-select towers when clicking on blank terrain.
A good start, though.
I wouldn't want to play it for long, but as a textbook example, it's pretty good. You may wish to include a sidebar of numbers being crunched for demonstration purposes.
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