Yes. While it’s not the usual situation that someone in a younger generation gives gifts to someone in the older generation, there’s no tax rule barring this. In fact, under tax law there’s no bar to gifts being made by minors.
A retirement account to which up to $4,000 (or $5,000 if you are 50 or over) may be contributed for 2007, but deductions for the contribution are restricted if you are covered by a company retirement plan. Earnings accumulate tax free.