Ali Collins, one of the top under-14 players in the UK and a scholar at Beaconhurst School in Bridge of Allan, Stirlingshire, met the former British number one last year.
The tennis world was devastated when she died from liver cancer earlier this month aged 30, and Ali organised the Rally 4 Bally event - a 12-hour tennis marathon - at her school to raise money for the charities Baltacha supported.
She invited Mrs Murray, mother of Wimbledon champion Andy Murray, and was delighted when the coach spent about an hour rallying with children aged as young as five at the event earlier this week.
About £1000 has already been raised from the day through a cake sale, sponsorship pledges and donations - with money still coming in.
Funds raised will be split between the Royal Marsden Cancer Charity and the Elena Baltacha Foundation, which supports the Elena Baltacha Academy of Tennis.
Mrs Murray said: "It was a fantastic day and it was all set up by Ali - who is one of our most promising young tennis players - and her friends, which is just amazing.
"Elena Baltacha left a real impression on these girls and it's just wonderful that they and all the coaches have come along today to raise vital funds for such a fantastic cause."
She later tweeted a photograph of the youngsters competing at the event with the words: "Impressive."
Ali, other tennis scholars and her coaches were on court from 8am until 8pm, where they played with other Beaconhurst pupils and members of the local community in exchange for a charity donation.
The 14-year-old, from Andy Murray's home city of Dunblane, said of Baltacha: "She was an amazing player and a really friendly person who took time to give me and some of the other Beaconhurst tennis players some good advice.
"It was really hard when I heard she had died and I just wanted to do something in her memory and to raise funds for the charities she supported."
Judith Ramsay, director of sport at the independent day boarding school for boys and girls, said: "It was all their idea and the school was pleased to help and support the pupils involved who were deeply affected by Elena's death. She was an inspiration to them and `Rally 4 Bally' was a real mark of respect and tribute to one of our greatest female tennis players."