Munk Pack bars are a great bars to put in kids lunches. Just note that some of their bars may have non keto ingredietns so dont assume all flavours are keto. ( ie pretzel and popcorn ones)
Here are the ones that are low carb:
https://amzn.to/4iBkeeY - almond butter
https://amzn.to/4jepZA8 - coconut chip
https://amzn.to/4lH6S3q - peanut butter