See the introduction post to this series on Theories of Change (ToC) here. And part two on linear and systems thinking approaches to ToC. In this post, I will list several different approaches that are advocated by social movement participants and thinkers.
The US union organiser and trainer Jane McAlevey identifies three ‘options for change’: advocacy, mobilizing and organizing.
McAlevey explains that advocacy does not involve ordinary people in any meaningful way, professionals (lawyers, pollsters, researchers and communication firms) are paid to do the work. She argues that advocacy fails to use the only advantage that ordinary people have over elites – large numbers. 
Mobilizing has become popular in the last forty years. She states that mobilizing is an improvement on advocacy because it brings large numbers of people to the fight. The downside is that they are the same people – “dedicated activists who show up over and over at every meeting and rally for all good causes, but without the full mass of their coworkers or community behind them.”  This is because a central group, sometimes a professional staff directs and controls the mobilization. McAlevey argues that the staffers see themselves, not ordinary people, as the main agents of change. Their aims are for enough people to show up to get a good photo to tweet and get media coverage.
Organizing for McAlevey “places the agency for success with a continually expanding base of ordinary people, a mass of people never previously involved, who don’t consider themselves activists at all – that’s the point of organizing.”  Their motivation for action is due to specific injustice or outrage. The main goal is the transfer of power from the elite to the majority – the 1% to the 99%. Campaigns are important in themselves, and they are essential for bringing new people into the movement for change and keeping them engaged. McAlevey argues that mass negotiations are needed, rather than the closed-door type of advocacy and mobilizing. Also, that ordinary people need to create the power analysis, design the strategy and be active in achieving the outcome .
See this post that goes into much more detail about what organising and mobilising are and the differences between them.
Hari Han in How Organizations Develop Activists: Civic Associations And Leadership In The 21st Century identifies three theories of change from her research: lone wolves, mobilizing, organizing. Loan wolves use advocacy strategies that do not require them to engage with others. They build power by becoming an accurate source of information and expertise. Mobilizers aim to maximise the number of people involved that already have some latent interest, without developing their capacity for further civic action. Mobilizers build power by focusing on transactional outcomes such a growing the organisation’s membership. Organizers invest in developing the skills and knowledge of people to engage with others and become leaders. Organizers build power by transforming the motivations and capacities of their members to cultivate greater activism.
Paul Engler during the US training institute Momentum’s online webinars describes some ToCs. These are organised under the categories of the ‘inside and outside game’. This is also known as the ‘inside and outside strategy’, which I will look at in another post. The inside game is known as transactional and the outside as transformational. Transactional politics is the steady accumulation of small victories. Transformation change occurs in more dramatically punctuated cycles that focus on changing broad public opinion, rather than securing a series of incremental gains . Under the inside game, there is: lobbying approach, politicians, services approach. Under the outside game, there is: structure approach, momentum approach, pre-figurative, hybrid – Momentum Driven Organising . In their book This is an Uprising: How Nonviolent Revolt is Shapring the Twenty-First Century, the Engler brothers also discuss the structure tradition, the mobilising of movements and momentum driven organising.
For Paul Engler and Carlos Saavedra from Momentum (US), the structure approach is union and community organising that creates organisational structures that can mobilise large numbers of people for demonstrations. They describe how organizing is about relational work, one on one meetings, to find the leaders in the workplace or community. Also, look to recruit people that have followers. The second part of the structure tradition is deep leadership development. They quote the American Civil Rights Movement leader Ella Baker and her work to develop indigenous leadership. The third element is the use of large targeted actions to put pressure on those that can give the campaign what it is demanding. They describe the structure approach as very institutionalised .
The momentum tradition developed from the 1970s Clamshell Alliance and has been used by several campaigns and social movements. It used consensus-based decision making to create loose structures to create huge action, e.g. the Occupy movement. It uses momentum through militant or escalating nonviolent action. This results in moments of the whirlwind – “a dramatic public event or series of events that sets off a flurry of activity, and that this activity quickly spreads beyond the institutional control of any one organisation. It inspires a rash of decentralised action, drawing in people previously unconnected to established movement groups.” 
Engler describes the pre-figurative approach as creating counter-culture or alternative institutions outside the system and seeing that as an influence of change. He explains that all the inside ToCs, structural and momentum traditions all think strategically, that is working to change institutions – corporations, market, political system. The pre-figurative approach is different, it is about living the revolution – lifestyle and being the change. Not aiming to change the government but live the revolution. 
Momentum-driven organizing can best be summaries from the quote below from the book. These posts on the book are useful:
“Momentum-driven organizing uses the tools of civil resistance to consciously spark, amplify, and harness mass protest. It highlights the importance of hybrid organizations, such as Otpor and SCLC, which can build decentralized networks to sustain protest mobilizations through multiple waves of activity. It goes beyond transactional goals by also advancing a transformational agenda, and it wins by swaying public opinion and pulling pillars of support. It is attentive to the symbolic properties of campaigns, showing how these can sometimes be just as important as instrumental demands, if not more so. It uses disruption, sacrifice, and escalation to build tension and bring overlooked issues into the public spotlight. It aspires, at its peak, to create moments of the whirlwind, when outbreaks of decentralized action extend far beyond the institutional limits of any one organization. It is willing to polarize public opinion and risk controversy with bold protests, but it maintains nonviolent discipline to ensure that it does not undermine broad-based support for its cause. And it is conscious of the need to work with other organizing traditions in order to institutionalize gains and foster alternative communities that can sustain resistance over the long term.” 
Hackney Unites, a community coalition for social justice produced ‘An introduction to community organising’ that lists several theories of change. It frames them under ‘movement ecology’: “it is the larger ecosystem we’re part of. Beyond our organisations, there are many campaigns, movements, cultures, communities, and institutions that are trying to make positive change in their own ways (equally there will be people who are seeking to preserve the status quo, or even put change into reverse).” Hackney Unites explains that we are “integrally connected to a network of change makers with diverse approaches to creating change.” 
Hackney Unites list five theories of change in ‘An introduction to community organising’. I have summarised them below, see the Hackney Unites document for more info:
1. Personal transformation – “when we heal these hurts and take a step toward personal liberation, wellness, or enlightenment, we are more capable of healing and supporting those around us.”
2. Alternative Institutions – “Alternative institutions create change by experimenting with alternative ways of doing and being in the world: time banks, worker cooperatives, communes are some examples.”
3. Dominant Institutional Reform – “this theory assumes that change can best be effected by reforming dominant institutions such as governments and corporations. Because of their size and power, when they change, it can change life more significantly and for more people than by other means.”
4. Transactional organising – “this theory, largely accepts the status quo, the existing power balance, but suggests that if we get our communities better organised, then we will be able to more effectively bargain for with decision makers.”
5. Transformational organising – “is theory asserts that when people get organised, they become different people, and the society they live in becomes different, it moves to different rhythms and obeys different rules. The very process of creating well organised communities so fundamentally shifts the balance of power that those in power feel the need to behave differently, even before a formal demand is made of them.”
The Hackney Unites document gives an important word of warning – “these are all descriptive theories, and as with every set of classifications, they are only of use if we use them to order our observations of what actually happens in the world around us. These theories will lead us astray, if we rely on them to the extent that we ignore the reality of the world and instead try to force it to conform with the theoretical categories.” 
- No Shortcuts: Organizing for Power in the New Gilded Age, Jane McAlevey, 2016, page 9
- No Shortcuts, page 10
- This is an Uprising: How Nonviolent Revolt is Shapring the Twenty-First Century, Mark and Paul Engler, 2016, page 103
- 33m https://www.youtube.com/watch?v=etE_yml5xOY&list=PLeJeAirMA52rCePt4WuuZPD1WXb2Jnd5H&index=8
- 10m https://www.youtube.com/watch?v=4VMyg_TnMXE&index=1&list=PLeJeAirMA52rCePt4WuuZPD1WXb2Jnd5H
- This is an Uprising, page 177/8
- 37m https://www.youtube.com/watch?v=etE_yml5xOY&list=PLeJeAirMA52rCePt4WuuZPD1WXb2Jnd5H&index=8
- This is an Uprising, page 283
- An introduction to community organising, Hackney Unites, page 23/24
- An introduction to community organising, page P24