Some of your ideas so far:
I play a game with my daughter called 40 winks. We each have a grid with 40 squares and in each square you write a thing that the other must do.These can be as simple, diverse or funny as you wish. Every day you pick a number & have to follow the instructions. Very simple, not expensive & great fun. It's a summer tradition with us now.
A shallow, stony river, preferably with some tiddlers wins out over the most high-tech playpark everytime.
Get them tidying up bedrooms and/or playrooms. Make them bag up all old/unwanted items for a car boot sale. After the sale split the proceeds and let them loose in a toyshop to buy what they like
Built my son & friends a pair of 7 foot long by 2.5 foot high ramps in the back garden , for use by skateboards and skates , usage is heavy ..
Organise a day to meet with other school chums and parents for a picnic. The day before bake cakes, buns; make jellies and such like. Two days solved already! My daughter and I go to the local garden centre, where the bedding plants are now half price and I let her choose which ones she would like and let her plant them in her part of the garden.
Kirsty, Wakefield, UK
A Treasurehunt. Write down clues, which can be questions, riddles, puzzles, etc. and make the first clue give the location of the next and so on, eventually leading to a simple reward such as sweets. For young children this can all take place in your home and/or garden.
Baking buns: 1 pot of fruit yoghurt - keep this pot it's the measure for the other dry ingredients; 2 pots of caster sugar; 3 pots of self-raising flour; 1 pot vegetable oil (eg. sunflower); 3 large beaten eggs. Put all ingredients into one bowl, let the kids beat the living day lights out of it until blended into a smooth batter. Spoon into bun cases (3/4 full), bake in preheated oven at 180C (or equiv) until golden and springy when pressed in centre. They can be simply decorated or eaten plain.
Paper puppets. Fold a piece of A4 paper into four. In each space, the children draw and colour a figure from a favourite story using felt tip pens. Cut out the figure and attach a straw to the back with tape, so that the child can use it as a handle. We've had endless puppet shows from behind the sofa. Also, the children's character list is endless... They keep drawing more and more.
For long wet spells, go camping indoors. If you have a room big enough you can actually pitch your tent in it if it's a freestanding one. Otherwise, just arrange chairs and blankets into a tent and let your imagination go - have picnics there, "explore" the rest of the house with binoculars, etc. and then let them sleep there overnight.
Lynn Fortin, UK
For older children, my local recreation centre offers a 'fit ticket' which costs around £25.00. this allows unlimited use of the pool in public swim times for the whole holiday, also use of the gym and aerobics classes. Very useful.Others might do the same.
Nicki Scammell, England
During the summer my mum would take me round the market and buy me a few cheap tshirts and some buttons, sequins, feathers, glitter and fabric paints to make my own designs. I always loved that.
Write of list of things to be found in the garden; ie: a flat stone, a pointed leaf, a pink petal and get the children to go out and find them.
Our local university (York) runs a sprorts camp throughout the holidays so we let our children go there for 2-3 weeks which then allows us to have the other 3 weeks off as a family either on holidays abroad or just days out. The sports camp is relatively cheap and allows children to play 3 different sports every day
Contact your local authority and see if they have any subsidised activity or sports schemes for the holidays. Ours have lots of activities and sports coaching for £3-4 a day. Or they can put you in touch with charities or others running playschemes which are often free or of minimal cost.
Mrs. M. McKeever, UK
Aim to really tire them out during the morning, eg. park trips, swimming, bike rides, walk to the shops (not drive) with a treat at the end. Then sit them in front of a video mid to late afternoon and have a break yourself. By then they'll be tired and more amenable and you will get a well deserved rest.
I bought each of my three early teenage children a disposable camera for the summer holiday. I asked them to look for images that really interested them, and arranged for a family friend - a photographer himself - to choose the 'best' image without knowing who'd taken what. This project kept them thinking and looking all summer holiday and raised visual awareness.
Laurence Vulliamy, UK
Try the Krypton Factor in your garden, it gets the kids thinking the idea is to lay a course such as a plank, bricks, as stepping stones around the garden then get the kids to follow the route without touching the grass and retrieve several objects around the course, such as a bucket, a toy etc.
Write down a list of challenges, award stars for completed ones. They can be a mixture of indoor and outdoor things, eg. collecting wild flowers, making a model from junk, writing a story, throwing and catching a ball with a sibling. Prize at the end of the summer for the child who has completed the most challenges.
Get cheap fabric bags/t-shirts/old clothes and let the kids loose with glue, feathers, buttons, glitter and other bits and bobs so that they can create their own designs. Cutting up old jeans and decorating them used to be a favourite hobby of myself and my sister during the holidays!
check out local press many local authorities and charity groups run holiday play schemes in local parks which are often cheap or free.
Maggie O'Neill, UK
Get your children to join the scouts or guides.
Most scout and guide groups take off for a week to camp during the summer holidays, as well as all the other activities they do throughout the year.
How about a drink stand? It costs very little for the drinks, and kids will be entertained for hours mixing the juice, setting up the table, and recruiting customers. Plus they feel great when it is all over and they have earned some money of their own (even if it's not very much).
Tell us your top ideas for children's cheap and fun summer activities.
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