Ebi-kun was given a slugs kit for Christmas which we had put away for a rainy day, it was a rainy day so we got it out, I think it was all the slugs that are eating out strawberries that reminded him about the kit. There were two pots of slime, we liked the green more than the yellow, which was runnier, in the pack it gave some ideas on how to use it and the scientific blurb.
After letting it dribble through his fingers then pulling it slowly then quickly to see the difference. We got out straws and tried blowing into the slime, this did look somewhat like bubbles of snot! and DON'T suck, that would be revolting! We also tried rolling it into balls and making in bounce.
The kit also included a slug mould, you pop the googly eyes in then pour in the slime and flip it over...
Pull up the mould and watch the slugs spread out like they are melting.
It was a pretty horrible activity but Ebi-kun enjoyed it, it did seem to take forever to clean it up! I am sure you can do most of this without a kit, a simple google will turn up several slime recipes and although Ebi-kun didn't really like feeling it, it is a good sensory experience.