My 4 year old loves hidden picture activities. And when her monthly Friend magazine arrives, that is the page she looks for first. I went through all the back issues we have collected and cut out the pages with hidden picture and other fun activities.
I pulled out this plastic scrapbook binder and filled it with clear protector sheets. (The glossy kind) Then I filled the pages with her activity sheets.
I got carried away and made some travel bingo sheets as well as some wooly willy-type faces of our family that she could draw in hair and features.
Add one dry erase marker, and something to erase (I taped coffee filters to the end in a bunched up flower looking shape) and you are ready to have fun, erase, and repeat.
I think these would also be excellent quiet books for church, or busy books when you eat out to keep them busy at the table.