It is easy to have your kids be involved in the thank you note process, no matter what the age.
For the very young: Write thank yous for the gifts your young children have received on note paper made from their own drawings. Let kids fingerpaint or color on blank notecards or on regular paper that can be cut down or folded to fit in an envelope.
For toddlers and pre-schoolers: Let your child ‘write’ the thank you themselves. Then ‘translate’ the scribbles into readable English. If the kids are starting to write their own names, let them sign the thank you note.
For primary ages: Kids can draw a picture of the gift (wearing the sweater from Grandma or playing with the toy from Uncle Matt) and you can write the thank you words they dictate to you. By this age, though, many children should be able to start writing sentences. A simple Thank You Frame (see below) is appropriate for this age.
For older elementary kids and above: By the time your child is in fourth grade an above, they should be capable of writing thank you notes themselves. One strategy for getting kids to get thank you notes done is to not let them use the gift until the thank you has been written. Another idea is to set aside one morning or afternoon for thank you writing. Put all the supplies that kids will need (pens, pencils, paper, envelopes, stamps, addresses, gift lists) on the dining table. Sit down as a family and have everyone complete their holiday thank you notes. You can do yours at the same time and be a good model for your kids!
All Ages: Take a digital picture of your child with or without the gift and attach it to an email to the giver. Or print the picture on regular paper and use that as your stationary.