You will need:
Egg carton
Cereal box card (for the legs)
Plain white paper
Black marker or gel pen
PVA craft glue
String
Yellow or green tissue paper
Black pipe cleaner (optional)
Strong glue (like UHU) optional
1. Roughly cut the cones out of the egg carton base, without cutting through the sides. This needs to be done by an adult. You could use nail scissors or similar to pierce a hole. It's easier to make the hole and cut around the bottom of the cones from underneath (see first pic), but it still takes a bit of effort to cut through the cardboard joins.
Also, pierce a hole in the middle of the egg carton lid (for the string) Make this hole about pencil width, so the spider doesn't get stuck on the string.
2. Paint the egg carton, one of the cones (for the fly) and the cereal box card black (about 25cmx15cm/10in.x5in.)
3. Working on the spider first, once the paint is dry, cut eight strips for the legs. Make them all as close to the same width as you can, roughly about 1cm/1/2in., and keep them nice and long - about 20cm/8in.
4. Fold all the legs in half, crease in the middle then open up again.
5. Glue four legs on each side of the inside of the egg carton base. Spread them out evenly around the sides.
6. Decide which side is going to be the front of your spider. Cartons have different cardboard catches at the front, to keep them closed. Ours had two, so we cut off the sticky-out card catch bits on the base, and used the holes in the lid for eyes. Either snip the holes to a shape you like, and stick paper eyes behind them, or, simply make sure the eyes you draw are big enough, and stick them over the holes.
If your carton has one catch at the front, you might prefer to stick your spider's face on the back of the box, which would work just as well.
7. Draw eyes on some plain paper and cut them out. We wanted to make our eyes look a bit scary, and drew the black pupil right at the bottom, so the spider looks like his eyes are fixed on his prey..
Cut out some zigzag fangs too.
Glue on the eyes, and glue the fangs just under the edge of the lid at the front of the carton, or just under the ridge if you're using the back of the carton.
Glue the egg carton shut.
8. While that's drying, make the fly.
Cut around the bottom of the painted egg carton cone to neaten it off, so it's about 3cm/1in. long, and cut it in half lengthways.
9. Cut the fly's wings out of the spare, unpainted egg carton cone. The sides of the cone already have a winglike shape, they're just a bit long (but perfect for the dragonfly we made recently on Instagram) So make them about half the length of the cone. Cut out two.
10. Cut the bottom of the wings at an slant and glue on top of the fly's body, so they make a little 'v'.
11. Scrunch up small pieces of yellow tissue paper and roll into little balls for the bulgy eyes and glue in place.
12. You can leave your fly as it is, or add pipe cleaner legs if you want. Cut three similar lengths - long enough to fit underneath, and protrude either side. You will need a stronger glue (like UHU) or a glue gun to attach the pipe cleaners. You may want to turn up the sharp ends of the pipe cleaners too, so bear that in mind when you are cutting the three pieces.
13. Once it's dry, cut a good length of string or yarn, thread onto a needle and make a hole through the top of the fly, roughly in the middle, between the wings. Thread it through, remove the needle and tie a knot in the end of the string, so the fly is attached.
Feed the other end of the string or yarn up through the bottom of the spider and out through the hole on top.
Simply pull your spider to near the top of the string, make the fly dance around in the air or on a table, and then drop your spider...
The length of string really depends on how far you want your spider to travel. Maybe from an upstairs landing would be fun... dangle the fly until someone downstairs spots it, and then watch them jump!