This is cool science !  There were no real instructions for this pretend play  just a buffet of fun things safe to mix in experiments.  My son got into this right away taking on the serious personality of a chemist as he dove into his imagination. This is so easy to do because all you really need is water and a few kitchen tools, everything else is just icing on the cake.

1. Gather your materials. For our science lab we used a handful of glass jars -if you are really keen you can put graduated measurements up the sides, but remember kids imaginations don’ need every detail done for them.  You may want a few absorbent place mats, turkey baster, eye droppers, small measuring cups,  mini whisks, some shampoo or dish soap , some baking soda , water and food color.  Also eye protection and an apron or lab coat is a must!
2. I added a few drops of food coloring in jars of water and set everything out – something I learned years ago is if everything is at arms reach fewer things spill . If I was doing this with multiple kids I’d ditch the chairs and have them stand at a low table.
3. Start concocting! 
4. The baking soda mixed with the shampoo made a nice ( not overly) fun fizzy foam, clearly the shampoo was acidic. This made me remember doing a science experiment in grade 4 with all sorts of things and mixing them with baking soda to see which was the most acidic. If you want you could incorporate that too.
5. Keep going!  He had a blast.
6. I got a tub ready to soak everything in after playing.
7. We had so much fun I had to dump out his beaker and get him some new yellow water.
8. Popped them all in the water – we let them soak and came back later to scrub. See this activity includes practical life and water sensory play too.