Start by mixing 250g of the yogurt with one teaspoon of the maple syrup or honey. Spoon the yogurt mixture into an uncut disposable piping bag. Close the top of the piping bag and secure with a rubber band. Pop into the freezer to keep cold and frosty until ready to use.
Make up the coloured fruit layers; place the pineapple in a high speed blender with a third of the remaining yogurt and a teaspoon of maple syrup or honey. Whizz together until smooth. If you're having trouble blending it, add a splash of milk to help loosen the mixture the continue to blend. Taste the mixture for sweetness - you may want to add a little more maple syrup or honey until it tastes how you like it.
Spoon the pineapple mixture into a piping bag, tie up and pop in the freezer to keep cool as before. Repeat with the blueberries, and then the strawberries/raspberries, rinsing out the blender well between mixtures.
When you have all 4 mixtures ready, get out your popsicle mould and remove the full piping bags from the freezer, ready to be assembled. Cut the end off each piping bag and carefully pipe alternate layers and blobs of the different coloured mixtures into the moulds, taking care not to mix them up too much as you do so. Continue until all of the moulds are full.
Place the lid on the mould and press the popsicle sticks in place. Place the mould into the freezer for 2-3 hours or overnight until the popsicles are set and frozen through.
Once frozen solid, carefully remove from the mould and serve immediately, or place popsicles in a freezer bag and refreeze until ready to eat.