Making slime from a leftover pumpkin

A simple scientific experiment for your happy Thanksgiving Day!

Warn­ing! Only un­der adult su­per­vi­sion. Do not eat the slime or the pump­kin used in the ex­per­i­ment.


  • left­over pump­kin;
  • glue with polyvinyl al­co­hol;
  • con­tact lens so­lu­tion;
  • bak­ing soda.

Step-by-step in­struc­tions

Add some PVA glue, con­tact lens so­lu­tion, and bak­ing soda to some left­over pump­kin and mix thor­ough­ly – this cre­ates an amus­ing or­ange slime with pump­kin seeds in­side!

Process de­scrip­tion

Glue used to make slime must con­tain polyvinyl al­co­hol. This com­pound con­sists of mol­e­cules with a huge num­ber of spe­cial frag­ments. Just like small hooks, these frag­ments catch on the mol­e­cules yield­ed by the re­ac­tion be­tween bak­ing soda and boric acid (which can be found in con­tact lens so­lu­tion). They form weak chem­i­cal bonds, but in a huge quan­ti­ty, so the glue thick­ens rapid­ly and turns into slime. Want a fun Thanks­giv­ing sto­ry? Make this slime and leave it in a hol­low pump­kin with­out telling any­body. A friend or two might be very sur­prised to find that slime has formed in­side the pump­kin!

Even more amus­ing ex­per­i­ments to do for Thanks­giv­ing 2021 await you in the MEL Sci­ence sub­scrip­tion!