To help cut down on this, you can tie a knot at the end of each lace to keep them from being pulled out.
Another problem I often experienced was that the ends of the laces become frayed when the aglets (that's the name for the hard plastic "things" there) come off. This made relacing a nightmare.
To combat this, you can take a one inch piece of scotch tape, press the frayed end on and flatten against the sticky side, then roll very tightly. Now you've made your own aglet, and lacing is a cinch.
If you find that your toddler is consistently pulling laces out, they may be trying to master their lacing technique. It's a fun skill to them. You can redirect this enthusiasm by purchasing a special doll, like this one, that allows for lacing, snapping, zipping and buttoning practice, or you can make your own lacing board out of some yarn and an old meat tray. If you're handy with the sewing machine, you can use this free snake pattern to make a practice toy. This way you've saved yourself some time (and maybe sanity) and your toddler still gets to work on his or her fine motor skills.
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