I used a Clifford theme in my 1st grade classroom for several years and the kids loved it! Here are a few ideas:
By Amy C.
Welcome Board: "Paws" To Meet Mrs. _________ Class!
I did a HUGE Clifford on red butcher paper and put each child's name on a paw print.
Behavior Board: "Behavior To Bark About"
I traced and chalked a picture of Clifford barking
and each child had a dog bowl with 3 different color bones (like green, yellow, red card system). When they did not follow the rules, they had to "bury" a bone(move a card).
Decorations: Use Clifford stuffed animals available through Scholastic or retail stores. I found Clifford pillows at The Dollar General Store. I also have Clifford bookends that are adorable. You can purchase them through Avon. I have seen Clifford plastic furniture at Big Lots.
My school supply store carries note pads that look like Clifford, they are red dogs. You can use these to put on their folders and write their names on them or you could use them for cubbies.
Hope you can use some of these ideas!