I often use the Piano Time tutor books with beginners – book 1 works well for beginners aged about 8 and upwards.
Did you know you can download extra pieces and sample pieces from the OUP website? This link
will take you to the page for book 1 where you can download sample material and extra pieces for book 1. If you carry on hunting around on the site (type Piano Time into the search bar) you can find more pieces from the other books.
I’ve found Prehistoric Piano Time and Spooky Piano Time to be popular books, and Going Places has some unusual and quirky pieces. Great for quick study, sight-reading, or to have in your stash for when you hear “I forgot my books…”.