Crochet in one colour or use up bits to form stripes. For stripes, 2 rows each of the subtle colours with 1 row of a strong colour makes a good combination. Use either all acrylic or all cotton fibres. I used DK cotton on a 3.5mm hook to make it a tight fabric texture.
Chain 60. (foundation row)
Ch2, miss first 2ch then dc into next stitch, dc into every stitch to end.
Continue until you have made 20 rows and your work looks like a rectangle. Fasten off.
At one end, which will be the opening, do 22dc across the end.
Turn work, ch1, dc 11 sts, ch2. These will be the lid/flap and you will be working on these 11 sts thus:
Miss the first chain, dc9, ss in the last st.Ch2 turn
Miss the first chain, dc7, ss in the last st. Ch2 turn
Miss the first chain, dc5, ss in the last st. Ch2 turn
Miss the first chain, dc3, ss in the last st. Ch2 turn
Miss the first chain, dc1, ss.
Chain 8 to make a loop (or however big your button is) and ss into the first chain to complete the loop.
Add a button and sew up the sides catching each stitch with its opposite one to make a neat edge. Turn the right way, insert the recorder and hand to a small budding instrumentalist.
Let me know how it goes, modify it, make it your own but I hope you have had some inspiration to get started. xxx