I used to include info about messy play such as making playdough or using soap flakes in my newsletters.
I then asked the children for feedback - did they get to do the things I was suggesting? The feedback was disappointing to say the least.
I then tried sending home small book / puppet combinations but parents were very worried about borrowing them in case of loss or damage and a few came back scribbled on by siblings or the children themselves despite our chats about respect etc.
Then I tried laminating song sheets for fave songs from my house and including a You Tube link so parents could learn the words / tunes etc. I asked parents for feedback and that didn't go down very well either. They are all busy people.
I then sent home a camera taking it in turns between the families so chidlren could make their own home photo albums. That went down slightly better - 3 families completed that one (out of a possible 7).
I have a new set of parents starting soon and thought I might try the recipes idea again... see if it is more successful second time round.
I hope that's what you are looking for
