How big are these raised beds? If they are 4 feet wide you may not need to be concerned about "winterizing".
Planting spring flowering bulbs with the idea that you can transplant them in the spring, if that is to be done before they are done for the year, is not a good idea since you can disrupt the plants regeneration when you dig them up.

Planting a winter cover crop in your raised beds is an excellent practice to improve soil fertility during the fallow period/offseason. And it will keep the beds weed free. Just till the cover crop in in early spring about 2-3 weeks before planting.

If you choose to use the beds for spring bulbs, plant the bulbs in containers, then sink the containers into the raised bed soil. When bulb season begins you can safely transfer the containers to areas of your garden where you would like a splash of color without risking damage to the bulbs or disrupting their growing cycle. And it is easy to remove them when the bloom season is over and the unsightly foliage gets in the way of other plantings.

This was our first year doing raised beds and was wondering what we should do for the winter with them and if I could palnt bulbs in them to then transplant in the spring?

Impossible to say with the info given .

Nonetheless, cover cropping is one way and we use erosion blankets to ensure our soil doesn't blow away. Not sure why you would want to transplant bulbs in the at zone, just plant them where you want them to go and let them multiply. If you want color while waiting for crops, sow red clover as a cover crop else set aside small areas for flowers.

Dan