It's likely the worst investment you'll ever make. They cost £100,000s, rarely give back or say thank you, and once you do it, you'll need to keep shelling out again and again (and again)... children!

Thanks heavens we love 'em though, and are desperate to do what's right. "What are the best kids' savings?" is one of the most common questions I'm ever asked, so I'll answer that for you, but I want to go further, with key things to think about that you may be unaware of...

Check if you're one of 800,000 missing out on £1,000s of help (even if you earn up to £100,000)...

This is about Ofsted-registered (or other UK nations' equivalent) childcare, including childminders, nurseries, after-school & holiday clubs, and more.

• Child aged 3 or 4? They're usually due a free 15 to 30hrs a week depending on which UK nation you're in and the hours you work.
  
  
• Family income under £40,000ish? First check if you're due cash to cover some childcare costs, using our Universal Credit (UC) calculator. Already claim UC? If you're in work, see if you're due up to 85% of childcare costs. On tax credits? Are you due up to 70% of childcare costs?
  
  
• Earn up to £100,000? Check out Tax-Free Childcare. If you can't get UC or tax credits, look at Tax-Free Childcare. Here, for every 80p you put in the scheme, the state adds 20p, up to a max £2,000 per child per year for up to 11-year-olds (16 if they have disabilities).
  
  To be eligible, you must earn equivalent of 16 hours minimum wage or more a week (if a couple, both of you must), whether you're employed or self-employed. See how to get Tax-Free Childcare.

Everything you ever wanted to know about saving for children, but were afraid (or didn't know who) to ask...

Sadly, when saving for ickle ones, many accounts pay ickle interest. So if your children have savings, do check now what they pay (if they're older, get them to do it, it's a good lesson), then up the rate. Full help in Top childrens' savings, but at speed...

• Top easy-access children's savings pays 3.75%. For age 7 to 17, HSBC's MySavings pays 3.75% AER variable on up to £3,000, with unlimited withdrawals. If parents bank with HSBC, it can be opened online, if not, it must be in branch.
  
  For younger children and / or larger amounts, Leeds BS's Youngsaver pays 3.65% AER variable on up to £1m, again with unlimited withdrawals for any child up to age 17. Your local building society or credit union can occasionally pip these rates. More help and options in Top kids' savings.
  
  
• Earn 5% on up to £100/mth. If you're regularly putting money aside, Halifax's Kids' Monthly Saver pays 5% AER fixed for a year for up to 15-year-olds, and you can put in up to £100/mth. You can only withdraw early by closing the account. More options in Children's regular savings accounts.
  
  As for fixes for lump sums, where money is locked away, these are rare, but Saffron BS currently has a 2yr 4.4% fix openable by post or branch for £500 to £25k.
  
  - Can grandparents open accounts? Yes with Leeds, no with Halifax, Saffron and HSBC, as it needs to be the parent/guardian or they need to sign. Yet in all cases, you'll need the child's ID (passport or birth certificate).
  
  - What about investing in shares & funds etc? That means you go for higher returns, but accept the risk you could lose some of your initial investment. It's not our expertise so we don't cover it, but I'm not against it, indeed if putting money away for a longer period, it's worth considering. We've some signposts in JISA investing.

• Top Junior ISAs (JISAs) pay 3.8% - check what yours pays. You can put up to £9,000 per tax-year in a JISA, and all the interest is tax-free. Once the money is in, it stays tax-free year after year, and is locked away, without access, until the child is 18, then it's their money.
  
  This is a boon if you want to save for their adulthood. Yet do remember your gorgeous baby now may be different at 18, and then it's their cash (so if you use it to save for uni, they may choose to spend it on an Amsterdam smoking trip).
  
  The current top payer is Coventry BS's 3.8% AER variable (max £9,000/yr), both for new savings and you can transfer in existing JISAs if they're paying less, which most are. There are also stocks and shares-based JISA investments. More help in Top JISAs.
  
  
• You can open and save in a pension for your child. If you've done everything else and are lucky enough to have cash left over, then opening a pension for your child's worth considering.
  
  Even those who don't earn (including under-18s) can get the equivalent of 20% tax relief in a pension. In this case, the maximum amount that can be put away is £2,880/yr, and pension companies would automatically top it up to £3,600 saved with the 20% from the state via what's called 'relief at source'.
  
  This money will be locked away until they're at least 57 (unless rules change). Yet as it's almost always better to start pension-saving earlier, as it has longer to grow, this is a great start, you could even do it for newborns (it doesn't need to be the max).
  
  The simplest routes are via a basic stakeholder pension or other personal pension (they can transfer it when they're older) or, if you want more investment choice, a SIPP.

PS: Prioritise family financial security ahead of kids savings... I think of this like the aeroplane oxygen mask safety warning: "Put your own on before your child's", as if you're struggling to breath (financially) you can't help them. So while a nest-egg for kids is great, that comes after sorting expensive debt, and ensuring urgent living costs are met.

Up to 1m have £1,000ish in savings but don't know it

UK-born children aged 12 to 20ish had a Child Trust Fund (CTF)  opened in their name with £250 (£500 for those from low-income families) automatically added by the state to it. This tax-free savings product, which up to £9,000 a year can be added to, can't be touched until you hit 18 (which is now quite a decent number of people).

• Lost track or weren't aware of the CTF? It's your money and there's an easy tool to reclaim it. To find out, either watch my 3min Child Trust Fund reclaim video, or read our full Reclaim your Child Trust Fund help.
  
  
• Child still under 18? Ensure your CTF pays max interest. Many have pants rates, but you can transfer it to get 3.8%.
  
  
• Child now 18+? What to do with it. See our Maturing CTF help.

Are your kids financially protected if the worst happens?

I worked this horrid stat out years ago, and haven't been able to face updating it since, but it's in the right ballpark. It means one in a class loses a parent. I was one of those.

It's why when friends who've had children ask me, as they always do, "where should I save for their future?", I check if they've got life insurance before answering. Families already struggling with dire grief can risk losing their income, standard of living or home if unprepared.

The simplest protection is explained in detail in our Level-term life insurance guide. This pays out a fixed sum if you die within a set term, but how you get it can make an enormous difference to cost.

For example, on Monday quotes for a £200,000 policy to last till children leave education (21 years) for a 45-year-old non-smoker were:

- Straight with a bank - £26/mth (£6,500 over the term).
- A comparison site searches for cheapest - £20/mth (£5k over term).
- Via an execution-only broker, which rebates its commission - £14/mth (£3,600 over the term). To get this, you usually pay a one-off £25 fee.

Yet that's for those who know what they're doing. Many should get advice due to complexities like 'writing in trust'. This can still be cheaper than comparison sites (but more than the execution-only). Full help in the guide.

There's a little-known credit that may be worth £1,000s

If grandparents (or other family members), unpaid or paid, look after their under-12-year-old grandchildren while parents / guardians work - the parents can apply for the "specified adult childcare credit", so the national insurance (NI) credits that normally go to an off-work childcaring parent go to the grandparent instead.

It won't impact the parent applying, as they'll be getting NI credits due to working. Extra NI credits can boost the state pension of those with gaps in their record by £1,000s.

- Applications can be backdated to 2011.
- You can't get it if you are already of state pension age unless... 
- ...you don't get full pension & were doing childcare before state pension age, so you can backdate to increase state pension.

As Mick tweeted me: "@MartinSLewis I can't thank you enough. My wife retired 5 years early to help with our grandchildren. She was 4 years short of a full state pension. We'll now save £3,000 from not having to buy missing years." By the way, do check Are you short of pension years?

Cash isn't king online. What cards should they spend on?

Independent spending is an important way to learn financial responsibility - as is choosing the right product, so why not do it together?

• From age 6, (FREE) kids' prepay cards give you control. Children's prepaid cards let you load cash online to the card you give to your kids (aged 6+) to spend on. Most have many functions so you can monitor spending, set limits, block certain categories and more. The most famous is GoHenry*, but it charges £35.88/yr (though via this link newbies get 6mths free). Others are cheaper...
  
  - FREE HyperJar* card can be used online & in-store, but can't be used to withdraw cash from ATMs.
  
  - 1yr FREE for existing NatWest (RBS/Ulster) customers. NatWest Rooster Money kids' card is free for a year if parents are existing customers (£19.99/yr if not, and after). It also has a feature to list chores your child needs to do to get their pocket money.
  
  - £5 card for Revolut* customers on its free plan. You create the card for a £4.99 delivery fee, then free after (max £40/mth free ATM withdrawals).
  
  
• From age 11, they can get a debit card. HSBC's 3.75% MySavings account also offers a debit card for those aged 11+ on its linked current account. Alternatively, Santander's 123 Mini* offers a card at age 13+ and pays 3% AER variable on the whole amount if you've £1,500-£2,000 in it (lower interest if you've less).

It isn't for tuition fees, but the hidden maybe £10,000+ parental living cost contribution. Even if your kids are wee now, use our calc to find out

When most under-25s apply for university funding, there's a means test of family income for most that's effectively a proxy for parental income.

In Eng, Scot & N Ireland, this means test directly impacts how much your offspring gets to live off (loan & sometimes grant) while studying. The reduction is an implied parental contribution (in Wales, the means test just dictates the split between loan and grant).

Our How much will you need to save for your children's uni? calc works for all UK nations. The reduction starts at family income of around £20,000 in Scotland & NI, and £25,000 in England.

PS: I'm not saying uni is always the best route, there are many other options including apprenticeships / degree apprenticeships. Just it's worth being prepared. And of course, funding rules may change too.

Teens are data fiends. How to feed the habit for less

Obviously the right and cheapest route would be to get one of your old phones and put a cheap Sim in it - good luck getting teens to accept that. Our Cheap Mobile Finder tool finds the cheapest handsets for you too. Here I just want to jot down a couple of notes about kids' mobiles - do also see the NSPCC for some good help on parental controls.

• If it's a contract, it must be in an adult's name. Under-18s can't sign up for contracts, so it'll be yours and you'll be liable, and you'll normally need to pass a credit check. Though at least all networks let you set a spending cap. See cheapest contracts.
  
  
• Pay-as-you-go (PAYG) is usually beatable by rolling contracts. Traditionally, PAYG was a popular parental option as it gives more control. Today though, one-month rolling Sim contracts (where your calls, minutes & data are renewed automatically each month) are cheaper, so you can get the handset separately.
  
  You will need a contract for this, but often there's no credit check (you can still set spending limits though). As for price, you can get unlimited mins & texts, plus 4GB data '£2.40/mth', 12GB data '£4.20/mth'. See cheapest PAYG and cheapest rolling contracts.
  
  
• Family smartphone insurance is cheapest via bank accounts. While standalone smartphone insurance is fine for one phone, if you've a few in the home, then for £13/mth (so £156/yr) some bank accounts cover all the family's mobiles, and travel insurance and breakdown cover too. See Packaged accounts.

Banks want younger people, hoping they can grab your custom for life... make 'em pay for it (& move once it's pants)

Student accounts allow those doing degrees, or in some cases level 4-7 apprenticeships, BTEC courses and more, to get them. Most banks launch their new offers in summer, so it's too early to tell you now what's coming. For those already at uni, check out the current top student accounts, as you can switch to get a free 4-year railcard and an up to £1,500 0% overdraft if it's better.

There are fewer 'special' offers for those not going to study, so you're looking at the normal top bank accounts. Most of the switching deals will require you to pass a credit check. If not, app accounts like Chase*, which don't credit check, give 1% cashback on most normal daily spending for a year. More in our Chase review.

Railcards, kids eat free, baby freebies, school hol flights

• £6 off Family & Friends Railcard code - gets a third off most train fares for grown-ups, 60% off for kids. It lets you and up to three friends travelling with you get 1/3 off rail fares, as long as you travel with one to four children (who get 60% off). See railcard discount code.
  
  
• Kids eat free restaurant deals. Whether Asda, Beefeater, Ikea, The Real Greek or more, see where kids can eat for 'free' or £1.
  
  
• Freebies if you've a newborn or one on the way. Baby essentials boxes, nappies and more. 47 tips in our Baby MoneySaving guide.
  
  
• Beat school holiday travel price hikes. From hidden booking dates to checking out overseas holiday dates, the Scottish trick and more, MSE Jenny has loads of tips to help in her Beat school holiday price hikes blog.