I've been to about a million PD sessions on Spiralling the Curriculum in Math classes over the last few years but I haven't heard much about spiralling in Science classes. This semester I had an opportunity to teach Grade 11 Physics (SPH3U) for the first time in a while and really wanted to give it a shot. This is what I came up with.
If you aren't familliar with Spiralling, this post by Mary Bourassa is what got me started with my 10 Applied Math classes a few years ago. It's basically rearranging the course in Cycles instead of Units. Each Cycle contains bits from each of the curriculum strands. The complexity of the course material increases throughout the course.
It's been a big success so far. Half way through the semester my students have already seen about 70% of the material in each of the strands from the course. There will be no need to cram in the Electricity unit or Sound unit at the end of the course since they've already seen a bunch of each of those strands. Also, Spiralling is much less restrictive in that I can change the topic whenever the students need a change and provides tons of opportunities to make connections between the different strands. My hope is that students will remember much more of the material at exam time and exam review will be relatively easy.
I've also used a combination of Peter Liljedahl's Thinking Classroom and the Flipped Classroom which has freed up class time for discussing and tackling difficult problems.
If you're interested in the what research says about the advantages of Spiralling, it mostly has to do with how students learn and Cognitive Load Theory. I recommend Make it Stick and How I Wish I'd Taught Maths.
Drop me a line if you want to discuss this more!