Grandparents gift to grandchildren (minor)

Hello,

For the AY 2017-18, my mother ended up in paying huge tax. Can she save paying taxes by paying some amount to my son as gift? If yes, then what is the procedure in:

1. Giving money to my son. Can she just hand it over to him or deposit in his minor account?

2. Filing tax for the AY 18-19 - Which section of ITR she can show this amount in order to save paying taxes

Can she invest on his behalf in mutual funds or policies? Will this investment would save her tax [probably not under 80C sections because she already investing 150000 per annum in ELSS]?

Please reply

Thanks,

Rohit