Calendar Module Web Hooey

A client of mine has a landscape company and mails out a wall calendar to his clients every year. It has pictures of his landscaping work and tips below the calendar on what they should be doing to their lawns for that month.

He wants to reproduce this on his home page in a small module with just the images and the lawn tips. The module should open with the current month's image and lawn tips by default and also provide a drop-down menu so visitors can browse previous or future months.

FYI: For simplicity's sake, I've built the textual tips into the image (as part of the image). I'm not a coder, but need advice on the best way to handle the implementation. I've asked a few developers and have gotten greatly-varying responses, so I thought I'd toss it out to you kind folks.

I've attached a mockup so you can see what I'm talking about.