BTW, there’s an official Colab notebook for lesson 1 too (see https://forums.fast.ai/t/lesson-1-official-resources-and-updates/27936 with Lesson 1 notebook for google colab ).
It does seem slow and for resnet34 I had to set bs=12 instead of bs=16 like they did, because I got a ‘bus error’ (ie. not enough GPU memory). For resnet50 they set bs=10 which works.
It feels to me that using resnet is a cheap trick. Your training is not any smarter/faster, you are just building upon a huge pre-trained NN which is awe-inspiring but you have no way to control.