Yes they are very active fish. 5-6 males would do well in a 10g, provided that 10g was fully filtered, heated and had been through the nitrogen cycle.
10g is too small to mix both males and females, you'd end up with baby guppies coming out of your ears. While the first spawn may be cute and fun, by the 30th spawn and hundreds of unrehomable babies you may be pretty sick of guppies! So stick to males, they're the most colourful anyway.