Great ideas. I used to plant lettuce with my kids in the shape of their names. They were very proud of 'their' lettuce as it emerged. I also gave them each a bucket to collect rocks as a bit of competition (they were close in age) as I worked in the garden.
And canned with them -- I was quite offended when one son won a blue ribbon at our community fair for his green beans and the woman in charge smirked and commented that 'we all know' who really packed that jar. Huh? My son picked, cleaned, packed, and sealed his own jar with his initial on the jar lid so we would know whose was whose.