These actually sound like snail eggs to me. Your tetras are egg scatterers, and lay tiny eggs hidden in rocks or thick plants growth. You can see what their eggs look like in this video -- very tiny, and not protected in a gelatinous mass like the ones you've found. (Note that your tetras are an albino or leucistic strain of the ones in the video, but the same species, Gymnocorymbus ternetzi.) The danios I'm familiar with have similar spawning behavior, including zebra danios if that's what you have.
Corydoras eggs actually are sticky, but they're also not laid in a gelatinous glob. The ones I've seen are pearl or cream color and relatively large, about the size of a grain of couscous.
Check out this thread for some great pictures of both cory and snail eggs.
If they are snail eggs, then you don't really need to do anything special if you want to grow them out -- the hard part about breeding most aquarium snails is getting them to stop, really. I would just put them back in the main tank, maybe in a hang-on breeding chamber to keep the fish away. Personally I would be hesitant to let these grow out unless you know you definitely want them in your tank, because snail populations can get out of control.
Growing out fish eggs is a lot more variable, because fish employ so many different spawning strategies. Fish love to eat fish eggs, even their own, so isolating the eggs is a must in a community tank; it's common to see dedicated breeding tanks. From there, you'll then need to keep the eggs at the right temperature, and the water generally should be kept clean and well-oxygenated. It's common to see infertile eggs go moldy, so watch carefully and remove any that look fuzzy immediately; you can use methylene blue as a preventative anti-fungal agent. Fish eggs usually hatch in just a few days, depending on how warm the water is. Specific care instructions really depend on the exact species, so if they are fish eggs, you'll probably want to edit your question/title to include which are the parents (or if you can't ID them, a photo of the eggs).