You're looking to do price, so concert tickets and experiences can add up as much as gift boxes...so, here's the cheap plan
So, my suggestion to make Christmas Christmasy without breaking the bank...
1. 30 days of Xmas movies with hot cocoa - there are enormous amounts of awesome movies available for free everywhere - enjoy them this year as a family every night. If every night doesn't work, have it be a once a week movie night for all of December...
2. Go out to a Xmas tree lighting ceremony - every community has a free one
3. Volunteer for a children's Xmas party. Many locations offer these types of events and would love to have volunteers!
4. Have a week of festive baking - you can either eat your creations or donate them to local police and fire departments (or Church Vigil parties)
5. Play Christmas music in the house, early and often
6. Do a family Secret Santa...rather than everyone buy for everyone in your immediate family, have everyone select a name to buy a $10 gift for...have it stay secret and see what folks do on Xmas - takes the focus off the "under the tree" that might be lesser
7. Go to Midnight Mass - total Christmas experience
8. Save a special "trip experience" as a secret to gift on Xmas - it could be breakfast at Cinderella's Castle or just the FPs to the Avatarland rides (which are free, but hard to get)...