Two thoughts: (1) what about having everyone plant a strawberry planter, either with strawberries or with herbs, or design a patio planter ("thrill, fill, and spill")? Or more "craft-sy" -- how about the stone cast leaves from GardenGate magazine? I've made them and they are a lot of fun to do (and quite easy). I made them without the base, because I wanted to set them on the ground in my butterfly garden for butterfly "puddling" ... no idea how it works to make the base as well, but if you've got big leaves (rhubarb, petasite, sunflowers, hostas), these are easy and fun.

Here is a link that might be useful: Stone cast leaves

I can think of a some ideas you could incorporate. These are based on the most common gardening errors, or I confess, my ideas of ugly.
How about 5 simple things to beautify your garden
Right from Tracey d.s. deadheading.
Correct mulching techniques:
avoid mulch volcanoes (bad for trees)
keep mulch a distance from plant stems (promotes rot)
Choose undyed mulch
Do your friends use a lawn service? You could begin teaching them about "less chemical lawns or gardening"
How a mixed lawn is more beneficial to the health of insects animals and humans
What we now know about round up
Maybe the scope of these ideas is too big if the point is everyone has hands on experience.
Nevertheless, I think the idea of being a 'gardening coach' to a bunch of women is really exciting. In a quiet way, over time, you could really make an impact.

please tell us what you come up with, and best of luck!

You could also go the "healthy gardens, healthy families"
and ge

Gee, I'm so excited about your project I just cut myself off.
What about potted tomatoes- best planting depth, suckers, disease
As I said, good luck

Too bad your turn is in June. The first thing I thought of was showing them how to winter sow...

Hmm, I guess it's the wrong time of year to show how to take cuttings too?

I like Marty's idea of doing the leaf casts. Along the same lines, I was thinking maybe stepping stones or those little message stones (either painting them or using imprinted letters), but that might be too involved/expensive. I'm not sure of your budget or the size of your group.

Wreathmaking? Mosaics of some sort (stepping stones or small pots?) Ooh, how about painting terracotta pots and then planting something? A little succulent garden might be nice, but again, that might be expensive. Making a small water garden in a pot? Gee, sorry, all my ideas seem to include spending a bit of money.

A talk on composting? You could give them all materials to start with - that won't take any money, lol, just saving your kitchen scraps and grass cuttings, lol.

Espalier? Topiary? Bonsai?

Let us know what you decide to do! Good luck!
:)
Dee

If you have succulents in your garden, you could make succulent mosaics, dish gardens, or succulent wreaths with cuttings. Here's Martha's take on the subject: http://www.marthastewart.com/article/succulent-wreath
but you can do it with lower cost items with some scrounging. (For instance my metal holiday wreaths are still at the edge of the field waiting to be dry enough to pull apart and compost & recycle, and you can use less expensive materials than sphagnum, like hardware cloth or nylon netting such as bird net, or even landscaping fabric. Containers for a dish garden can be obtained at garage sales or Goodwill or your guests can bring them. Mosaics can be done in a wooden box or even those plastic nursery boxes covered with netting.)
Here are some links to inexpensive succulent hanger creation:
http://faroutflora.wordpress.com/2010/01/28/verticle-succulent-garden-from-found-object/
http://faroutflora.wordpress.com/2010/02/09/succulent-box-goes-vertical/

You could do decoration of clay pots or even basic plastic pots, such as sponge painting with acrylic paint so that it dries quickly enough to then plant. Other ideas include leaf prints on the pots, decoupage, drawing with acrylic markers or if you do a search there are quite a few web pages with ideas.

You could make some twig tuteurs, either from willow as the directions in the link at the very bottom suggest or from some other flexible branches like birch or with a vine of your choice or even commercial weaving material. Then give them some vining bean seeds to plant on them. Fine Gardening has another set of directions.
http://www.finegardening.com/how-to/articles/build-rustic-tuteur.aspx

Leaf printing on fabric (have your guests bring an item of their choice) with fabric paint and leaves from your garden are another possibility. Cotton bags, t-shirts, linens would all work with this technique, but cotton will take and hold the paint best.

If you have bulbs that need dividing, that would be a nice gardening lesson. You'd get your bulbs divided, and your friends will get bulbs for their own gardens. You could start cuttings of easy plants like coleus. You could plant vegetable seeds that do well when planted in June such as carrots that could be taken home either to then plant in the garden when sprouted or keep in patio pots.

Gardening with kids: seeds to plant, such as marigolds, beans and radishes. Potting up grape tomato plants in large plastic nursery pots you've decorated and added stakes to would be great also since kids would snack on those. Sunflower houses or bean tepees.

I think I'll be keeping track of some of the ideas in this thread for working in the garden with kids . . .

Here is a link that might be useful: making willow tepees

Even though it will be June - you could STILL teach them the concept behind winter sowing....just start annuals instead and give them the written instructions for what to do come winter.

I've taught winter sowing to children and we use the toilet paper tubes. If you go this route, you're also teaching about recycling - and (to some degree) composting since they can plunk the planter right in the ground.

What about teaching how to find seeds on flowers and keeping them?

Or some plant identification (especially the Leaves of Three)?

How about host & nectar plants for butterflies?

Starts for a sunflower teepee?

Short of ideas? There's a book called Roots, Shoots, Buckets and Boots that should offer some ideas you can adapt for a group.

How about heading over to the Garden Junk forum here, and teaching them how to make a simple piece of garden art?

Mosaicing is SUPER easy, and they could do easy-peasy garden stepping stones using cheap landscape blocks.

Garden Totems are also super-easy requiring only their old unwanted glassware (you know, those TABLES that you see at every yard-sale on the block) and a small tube of silicone.

Anyway, tons of ideas over there; good luck with your "slot!"

Here is a link that might be useful: Garden Junk Forum

If I could have attended a demonstration as a new gardener, the one that would have helped me the most would have been one on soil prep. I think it was several years before I really understood what it meant to prepare a bed well, or even to dig a "$25 hole" - if I have the amount correct from the old adage about a $5 rose. In early years I didn't really understand the value of soil prep. The difference it would make to these potential gardeners in terms of encouraging results might be substantial, there wouldn't be much needed in terms of supplies, but of course the down side would be that there wouldn't be anything to take home.

Wow. Thank you so much for all of the thoughtful responses. I know I will definitely use some of these this year, and save up other ideas for next year and beyond. I really appreciate the input, and will report back after my group to let you know what we did and how it went over. In the meantime, if there are other ideas, keep them coming, but if not, I've got a lot to work with here!

Hypertufa! I just saw a reference to it elsewhere while reading, and thought of this thread immediately! You could show them how to make a hypertufa pot. I sure wish someone would show me, lol.

:)
Dee