This highly depends out your budget, and number of recipients of gifts.
At the end of the school year, at the middle school where I was the president last year, we had a $1000 budget, but we catered sub sandwiches for the teachers in the school library ($600??) and had a raffle, I made up a black foam display board filled with numbers. There were the same amount of numbers as staff (we included everyone, not just certiified teachers, at teacher's request. On the back of the numbers printed in a light gray font was the gift. Most gifts were candy (a huge candy bar) , but 6 contained ($20-$25) gift cards (Walmart, Applebees, Movies, etc). This way everyone got something, and a few got something even better.
The gift part took about a week to organize. To make sure I had enought, I had a sign off sheet listing all staff members and marked them off as they pulled a number. It takes a while to get the list from the office.
We are a PTO group for a k-4 school and 5-8 school. For the k-4 group, we are making a wishlist Christmas tree on their door. When the parents visit the teachers during parent-teacher conferences, they can pick one. Our middle school does not have the same type of conference, so we are looking for a unique christmas gift giving idea.