There are endless number of things you can do using an empty egg pallet. One of the easiest and I guess the first thing that comes to mind would be that they make great finger puppets or faces. It is possible to use your drawn faces/people/characters/shapes in teaching in a classroom environment or at home too. You could draw shapes and ask your child to name them, you could ask your child to draw a certain shape, you may draw some faces that show emotions, you can make the drawn characters a part of a family, you can ask your child or your language students to tell you about the characters, you can ask your child/student to turn their back to you and as you tell them certain things, you ask them to draw them and then check how accurately they were able to do so (for instance, ask them to draw a smiley face and big eyes with a large nose and the hair falls towards left and has a tie etc. This involves a lot of language skills. Regardless of the language you are teaching, you can use it as a teaching activity), you can write numbers and see whether your child recognises numbers yet etc.
What I did with the last week's egg pallet was that I drew those simple characters on the inside and left it in Mr. Junior's play room at night for him to find it in the morning. When he sees something different, it always makes him curious. It wasn't an exemption this time either. He found the pallet in the morning, opened it up curiously, was surprised to see my drawing in it. He first spent some time alone and then came to me (I actually watched his first reaction without him realising it). We talked about it and I asked him to tell me about them. Their emotions, their names, their occupations, their clothes, their relationships to each other etc. He is only a young child with limited vocabulary and comprehension skills but he was happy to tell me about them as much as he could. It definitely made him busy for a while and I think he liked it even better when we had a 'conversation' about it. (He had a go at drawing as well after that but the pen he was using wasn't the best and he stopped trying it. He told me what to draw and I drew them at the back.)
As I mentioned above, there can be various ways of using this activity. I have just shared what I did only a few days ago as well as some other possible activities that came to mind. Looking forward to your comments on how you use/suggest using an empty egg pallet to keep your little ones busy or while teaching.
Enjoy your weekend!