“A retired farmer has spent more than 30 years building an enormous scale model of Herod’s temple – and it is still not finished” – A model of biblical proportions – Telegraph

Gamaliel the Elder (or Rabbi Gamaliel I) was indeed the grandson of Hillel. He is in the “House of Hillel” tradition which tends to be less rigourous than the “House of Shammai”. It would, therefore, be the traditions of Hillel in which Paul was schooled.

Not a lot is known about Gamaliel’s distinctive teachings.