The life insurance offering the lowest prices for your family would be term life insurance.
However, term life is temporary, so it only provide life insurance for the duration of the "term" you choose when you purchase your plan.
Most term life plans offer life instance protection for a period of 10, 15, 20 or 30 years. So, if you need life insurance until the kids are grown and on their own, or until they mortgage is paid off, this may be a good option for you.
The other option is permanent life insurance which costs about 2-3 times more than term life, but it provides guaranteed lifetime coverage.
If you need the most life insurance for the lowest cost, and you need coverage for 30 years to less, then a term life policy can help.
Level term life insurance has premiums that stay the same each year for the entire term of your policy, and the amount of life insurance remains level until your life insurance coverage ends at the end of your term.