Many sites offer a single month at a time. That works okay since people only print one month at a time. Downloads are usually in Word, Adobe, or Excel. Which you use depends on which software you are comfortable with. If you know Excel best then get an Excel calendar. If you are very good with Word, there are formats available which can be adjusted on the screen. It takes some practice to add notes to any template, but it's not too bad with practice.
You probably can find books or magazines containing word jumble puzzles, but you may prefer to create the puzzles yourself. Creating the puzzles yourself has the advantage that you can customize the puzzle for different occasions, pick words suited to your child's reading level, and tailor the puzzles to your requirements (for example bu avoiding hard_to_find diagonal words in puzzles aimed at younger children). Creating puzzles yourself is possible using nothing more than a pen and paper, but you'll find it incredibly time consuming _ so a better alternative may be to use your computer and some word jumble maker software _ that way you can simply enter a list of words, and the computer will generate the puzzle automatically.