I was never a big fan of Jell-O as a child which, given that I was born in the 1960s meant that there were many desserts of the combined Jell-O and Cool Whip variety that I missed out on.
That said, with all the food issues these days, prepackaged gelatin dessert cups are very popular at schools. They are sealed, nut-free, dairy-free, soy-free, gluten-free, seed free and due to their general lack of natural proteins (with the exception of animal gelatin) they are devoid of most allergens. And they have sugar and are colorful so kids will eat them.
That said, they are not approved on the Feingold diet, they cause issues for observant Jews and they are not only not vegan, they are not even vegetarian.
However this problem has been recently solved. Whole Foods stocks the Cool Cups brand and Trader Joe’s are offering house brand Black Cherry and Orange flavored Gel Cups that are Vegan, Kosher, and free of all artificial colors, flavors, and preservatives. They both use carrageenan as a gelling agent. Carrageenan comes from seaweed. You can learn more about it and the Cool Cups gel cups at their website which is located here…http://www.cool-cups.com/Cool_Cups.html
I did a comparison taste test between the two brands. They taste remarkably alike. I preferred the texture of the whole foods offering but was happy with both. You may let pricing be your guide. My son was just happy to be eating a gel cup with his pals, as was his vegetarian friend.
If you are looking for a reasonably “healthy” vegan gel dessert, I recommend them both. They do need to be kept refrigerated since they are made out of actual food without preservatives and real food does not have an infinite shelf life.