Per product coupon rather than per order

I know this question has been asked in one form or another, but I haven't been able to find the answer to my specific needs.

The site I'm building involves student registrations for classes. A single order might include registrations for multiple students. Not all students will qualify for the discount. Ideally, I'd like a promo code field in the product info so it's applied to the product as it's added to the cart, but this functionality doesn't seem to be present.

Alternatively, I'm not opposed to adding my own code to adjust the product price when the Add to Cart button is clicks. I haven't yet found the perfect place to insert the code. I'm also concerned that this wouldn't work, as the price is most likely drawn from the database at checkout time, rather than handled separately.

Incidentally, I have a sight in place that I've written from scratch that does exactly what I'm looking for, but we're moving to Zen Cart because we want the more robust features, and I'm sick of writing code from the ground up. I'd like to be able to plug in my Promo Code script and make it work, but I'm betting that's asking a bit much.

So... any suggestions? Wait for the next release?

Thanks!

Discount coupons in zencart can be both product-specific and time/date-specific, as well as being further restricted by number of uses (in totality, and by # of uses per individual customers).

The redemption code is entered at checkout because strictly speaking this is an ORDER TOTAL function... but yes... you can have coupons applicable to a specific product.

schoolboy:

Discount coupons in zencart can be both product-specific and time/date-specific, as well as being further restricted by number of uses (in totality, and by # of uses per individual customers).

The redemption code is entered at checkout because strictly speaking this is an ORDER TOTAL function... but yes... you can have coupons applicable to a specific product.

Yes, however a class registration for a specific date is one product. I might have 3 students register for the same class (product). Two of whom qualify for a discount, one does not. All three classes are purchased in the same order. I don't believe the current version does this, hence my question.