I find that it’s often the easiest activity ideas that are the best. This fits that criteria. By making a Sprinkles Sensory Bag for your child or student, you can create an easy fine motor and sensory activity that also serves as a boredom buster. 
Sprinkles Sensory Bag:
Supplies needed:
- resealable plastic bag (sandwich or medium size*)
- cake sprinkles
- colourful duct tape
- optional: paper
*While you can use a sandwich bag, I find that the freezer bags in size medium are thicker and less likely to tear so that’s what I always use for our sensory bags.
Directions:
- Reinforce the sides and bottom of a zipper seal bag by folding duct tape over them.
- Pour in some sprinkles.
- Remove the excess air and seal the bag.
- Fold another strip of the duct tape over the top.
- Give the bag to your child.
Your child can trace letters, numbers, or shapes in the sprinkles with their finger. This will help reinforce learning and also give them fine motor practise.
If you want, you can write a letter, number, or shape on a piece of paper and lay the bag on top of the paper so that they can use that as their guide.
As far as sensory benefits go, this activity provides tactile, visual, and proprioceptive sensory feedback. If kids shake the bag, there is also a small amount of auditory sensory input as well. 
One of the things that’s nice about this is that it is safe for preschoolers and even toddlers because even if they are able to get the bag open, the sprinkles are edible. Of course, adult supervision should be used with all kids’ activities.
You may also be interested in these preschool fine motor activities:
Ball and Bands Fine Motor Activity
