As the school year kicks off, it's vital to make sure your children are properly insured, whether it be for losing valuable equipment or suffering a sports injury.

The average school bag's contents are worth an estimated £265, according to insurer esure, with some carrying in excess of £1,000 if children bring in iPods, mobile phones or consoles.

Whether you let your children take expensive items - and three in five secondary school pupils take in a mobile phone and nearly a fifth a handheld console - they still need covering for everyday items.

Start by checking that you have cover for personal possessions outside the home on your existing home contents insurance - phones, iPods and consoles should all be covered. If your child plays a musical instrument or takes part in sports, either in or outside school, you may also need to buy extra cover.

If your child learns to play a musical instrument, the school may lend one, at least initially. If you are buying one new, violins cost around £75, clarinets £300 and electric guitars £150 for an entry level instrument.

First ask if your home insurer would cover it under the personal possessions section. Direct Line for example says that musical instruments and sports equipment would be covered under its personal possession cover, although bats and racquets are excluded if damaged whilst in play.

Some companies offer specialist musical instrument cover. You need a plan that covers new for old replacement, damage whilst in transit and cover abroad.

Orchestralguard 4 Schools from Pavilion starts at £30 a year for any orchestral instrument such as a cello or flute worth up to £1,000 and covers accidental damage and theft (including in car theft) for children aged 8-18.

If they are younger an Orchestralguard policy is taken out in the parent's name and cost £35 a year for the same level of cover. If your child plays guitars, drums or other electric instruments Musicguard cover starts at £55 for instruments worth up to £1,000.

Allianz offers ClassicPlay and PowerPlay depending on the type of instrument played. Premiums start at £30 a year for instruments worth up to £1,500.

Insurance broker Lark also has a plan but minimum premiums start at £67.75 for a violin worth up to £5,000 or a guitar worth up to £2,000.

Some 180,000 children aged 5-14 years old are injured playing sport each year. Some local authorities offer cheap insurance for sports injuries. But if yours doesn't you should look for a personal accident policy. Youthguard pays out on death or disability and also smaller amounts for broken bones.

There are three levels of cover - bronze, silver and gold - and sports are split into three categories. The most basic cover for activities such as cricket and netball is £28 a year for bronze cover.

If your child plays rugby or rides horses competitively, the same level of cover would cost £42.10 a year. For the top-of-the-range gold cover for a footballer you would pay £84 a year. This also pays out for example £500 for a broken leg.

Insurance broker B Portwood & Co also covers children's personal injury, paying out up to £100,000 for permanent disability. Premiums start £42.50 for one child, but if your child plays rugby you will pay an extra premium.

SFS Group charges £7.50 a term for accidental damage cover with a maximum payout of £500,000 for permanent total disability. It also has a personal possession cover plan just for school children, which costs £16.50 a term for £3,000 of cover up to £39 a term, which gives cover up to £4,000 including a laptop.