Moldy smelling wood slices

Try using vinager and water on it.

place them in a box of baking soda, or cedar chips

They may still be damp, make sure you let them dry out. Once you are sure they are dry, put them in a box or something with a container with charcoal or baking soda in it and leave it for a few days to see if it starts taking out the odor. You may have to put in new to get out all the smell. If you need to, try wiping them down with vinegar and see if some of the smell is gone when it dries. Please check to make sure the colored pencil drawings are not harmed by the vinegar before you use it. Good luck!

How about some fresh air and sunshine? An oven on really low might help too or near a heater.

I would leave them out in the sun for as long as you can, watching to be sure drawings don’t fade. That works for me & I live in the Pacufic NW where we’re damp a lot.

Are the items sealed to the wood?

We had basement flooding during a remodel and the commercial bleachy sprays and commercial mildew sprays used by contractor and I used tilex and Lysol solutions and sprays helped resolve the active molds on many of our household furniture ( to include wooden bunk beds) and items that didnt involve paper or cardboard.

Alternatively can the wood slices be sealed... to seal off the odor? Modge Podge is a good water based sealer, if you decide to go that route I’d pours some from the container in a diposable cup as not to contaminate the commercial bottle If second third coats are needed or use for another product.

Wrap them in newspaper (only newspaper) and put them in a dark area for about a week. Odor should be gone when you remove them.

I have out washed and dried old handkerchiefs and doilies, that one we’re moldy, in separate ziplock bags with baking soda. In your case, I would place the drawing sides facing up so the soda wouldn’t touch the penciling. Best wishes ☺️

And baking soda is so cheap! Thanks

I hope you can come up with a solution. Dont give up, start with mildest less aggressive suggestions and evaluate. Ive gotten rid of second hand smoke and musty smells from second hand vintage items. Im confident you'll figure out a way. Good luck!