I've got a few Grandchildren that want to fish this Summer, and I'd like to set up a few rods for them. 
Due to their ease of use, I think a closed face reel like a Zebco 33 might be a good choice. Any suggestions?

I've got two Zebco 33's my wife and daughter use all the time. They are really easy to use, inexpensive, and require minimal maintanence. IMOA, they are the perfect reels for novice/beginner fishermen of all ages.

My choice for young anglers is an underspin reel. These offer the simplicity of a spincast (closed face) combined with preparing a youngster to move up to a traditional spinning reel.

I'm glad to hear the Zebco 33 is still pretty reliable, and they seem to fit small hands pretty well.

The underspin is a great idea too - I hadn't considered how easy the transition would be to an open faced reel. I've never owned one though, what would you recommend?

Check out Bass Pro. They have several Bill Dance/Zebco Crappie Spincast and Triggerspin(underslung) combos. Also Bill Dance (Zebco) Select 733 series, Select 33 series, and Select Triggerspin series. Some of these may fit the bill.

On the flip side, using a reel like a 33, one is working the rod just the same as if he (or she) was using a casting reel. You used to ba able to get extra spools for the 33 and use more than one line size, maybe that can be done with underspins also??

I set up all my grand kids with used Zebco 33's Made in USA. All the new ones are made in china junk. I went to flea mkts, and garage sales to get them, some for as little as $4 w/pole. Took them apart, cleaned & re-lubed, and they work like new. I got them some decent rods and they've been working flawlessly for over 8 years now. Can't beat that.

Thanks to everyone for sharing their advice!

Bill