For my interview I was advised to include work from my art foundation course, all 3 years of my exam and recent work and include as much variety as possible. I would suggest trying to cover as many aspects of art as possible including: painting, drawing (life drawing would be perfect), illustration, printing, installation, video, photography, digital work, sculpture, textiles, fashion, print for textiles, graphic design, ceramics, etc. I'd say quality + diversity is the key!! Bear in mind history of art is a totally different subject and you may be missing certain key skills which you will need to learn before you can teach. I'd suggest considering a one year foundation course which will introduce you to a huge range of practical skills you may not have come across. It's also fantastic fun!! I enjoyed my foundation year more than my degree!!